I have no friends but pens and AI. I have been a long time pigma micron #2 user and I was looking to switch to a fountain pen. I was originally looking to get the affogato but I couldn't find it anywhere so I went with its sassy sister Caribbean w/ Onyx and I was glad I went with that choice. It took just a few days to find the sweet spot and now that I have I love this pen. I would say it writes a bit thicker than the 02 pigma but not much. Shipping was really fast and I enjoyed the junk food that came with it. This pen is awesome!

Quick full circle story: I was introduced to the fountain pen life just a few months ago in May 2026 by a co-worker. She walked into the break room and handed me a pen and said, "Here, try this!" I happily scrawled down a few lines on her notebook and felt a feeling I'd never felt before. In all the years of school and work holding countless writing instruments, mindlessly scribbling words on to paper, I had never felt such an exquisite feeling writing with a pen.
The pen she handed me was a Twsbi Diamond 580 of which she allowed me to try 3 more of her pens of the same model in different nib sizes and ink colors (all Iroshizuku inks which I'm sure further enhanced how excellent this first experience was). One of the 580s I wrote with (not the first one, I think that one was in Affogato) was a ALR in Caribbean with Onyx; it was my favorite as looks go.
That day I fell in love with fountain pens instantly as I wrote with her pens. At the time I had no idea how special these pens were in the pen world. I'm not sure why I did not choose to purchase a Twsbi as my first pen considering how profound my introduction was. I've since purchase and tried a few dozen pens from other brands in this price range. It has been a true adventure.
Ok ok, I know, this is a review for the 580 in Caribbean.
After almost 3 months and a deep dive into the world of fountain pens, I finally pulled the trigger on a Twsbi; this Twsbi; the same model that inspired a truly beautiful new chapter of my life... and oh man, this pen is outstanding. It is a cut above anything I've written with even in price ranges exceeding it's tag. This pen writes with such fluidity and even flow. It is absolutely blissful in my hand; it feels like it belongs there. I could write with it for hours and hours; I have in fact done so! It is quite light yet has tremendous presence. The internal piston system is fluid and effective and such a pleasure to look at through the characteristic Twsbi demonstrator body. I enjoy its perfect balance; it's an engineering marvel. I love how it caps: 1 1/4 turns; brilliant!! The amount of attention to detail on the accents makes this pen stunningly attractive. It's my favorite finial!
I say with complete honesty, this is my favorite pen I own so far. My friend at work ONLY has Twsbis : 580s, Ecos, Minis. I didn't understand her obsession. I do now.
I'm going to go write with my Diamond 580 now. And you should go pick one up for yourself! Cheers!

I have two diamond 580 AL R’s they write a little wet, which I like they always start right up even if I haven’t used them for weeks. They are very dependable pens.

The 580 ALR is my most beautiful and satisfying pen in my collection. I now own two, one in EF and another in M nib. Everything about this pen just looks and feels excellent. If you are between the Eco and 580, I think the 580 is well worth it.

Despite my praise, I do have a few pieces of critical feedback:

1. My EF one did require nib work out of the box. It was incredibly unpleasant to write with, giving a lot of feedback in all directions. I could be mad about this, but as Doodlebud taught me I can learn to tune and adjust my fountain pen nib so I can live a happy fountain pen life. Its my best writer now after some polishing. The M required no adjustment.

2. The clip was way too tight to use on both of mine, and I wish the shape of the tip was more refined rather than having the sharpish edges. I did stretch one of them out, but its almost too loose now.

3. Replacement nibs from most places can only be found in polished stainless, so for color variations plan on moving over your matching metal collar from the old nib, and having a mismatched nib.

None of these critical items should rule it out from consideration, these pens still make me very happy.

This is my first quality pen and I just can't put down! Before this all I had was a cheap $10 Amazon pen. It may have been more of a novelty but still I loved writing with it. With a spark of renewed interest and a recommendation from a good friend, I found this little guy and couldn't wait to get my hands on it. And boy was I not disappointed!

The color is exactly as expected. The feel of it in my hand is like it was meant to be, and it writes so smooth it puts all other pens to shame. Needless to say, I'm ecstatic.

A couple of notable features that concerned me but turned out to not be a problem:
(1) Nib size - not being a well seasoned fountain pen enthusiast, I wasn't sure what nib size I should go with. I thought a Medium was what I wanted but I played it safe with a Fine. Glad I did because it came out more broad than I was expecting. I'd still like to experiment with different sizes but was afraid that getting a replacement nib would mean I'd have to sacrifice the grip of this pen, which I love. But I was wrong. The grip is just an aluminum sleeve that easily comes off when you unscrew the head, which means all the 580 grips are interchangeable!
(2) After filling my pen with ink for the first time I noticed that the piston **** has about a quarter turn of play. Of course I was worried I may have damaged it right out of the box. However, further inspection showed that it's just part of the engineering.

Simply overjoyed

Just got my latest TWSBI, a “Caribbean” blue that really looks it’s teal and a dark teal at that. Still, it’s a nice color. I’ll likely keep it. Just a bit disappointed it’s not a brighter, lighter blue. The real pen differs from the picture on my phone.

This is my second TWSBI Diamond 580, both purchased from Goulet Pens. An outstanding foundation pen at a great price! The pen itself is gorgeous. It holds a ton of ink. It’s easy to fill and clean. And it writes buttery smooth, and even makes my handwriting look better. What’s not to love! Excellent service, as always, from Goulet.

I was impressed with the presentation of this pen on the website and the real thing did not disappoint. The color is beautiful and the pen is extremely well made. The nib glides on the paper as smooth as silk. I couldn't be happier with my purchase.

…Just how smoothly the extra fine nib on this 580 writes. I bought this pen for ink drawing mainly because of its ink capacity (by the way, the reservoir filled completely on the first “twist”). I was so pleasantly surprised by how great this pen is as a writer!

The level of service from this small company is why I keep coming back. For the second time in about a month, I changed the nib size on an order, probably as they were packing it. In both cases, they were able to accommodate my change. Thanks, Goulet!

I recently bought a Twsbi 580 AL R, Carrobean blue with Onyx. This higher price 580 did not come with a wrench like a cheaper one I just gave to my cousin. Doesn't Twsbi offer a wrench with this pen?

Love this pen. Writes well out of the box, outstanding color and if you’re looking for a matching ink try FWP Tumultuous Tides or Diamine Inkvent Blue Peppermint.

The pen is exactly what I expected. The website accurately captures the product. The service from this site was excellent and I will be purchasing more in the future.

I love Twsbi pens especially the 580s

Looks beautiful and writes beautiful. Loving it. What more can I say

Always have to get the next color. I wish they would redo the 580 in Persian green
I just starting my fountain pen journey after they were sold out. Maybe, you guys could pass that along. :)
Love goulet pens. Learned so much from the videos.
Thanks guys :)

I have made a lot if purchases from Goulet Pens. The store has a wide range of items useful for anyone who enjoys writing with a good pen, using good ink on good paper. The staff there is very helpful; they get orders out in a timely fashion and tracking orders is easy. I highly recommend Goulet Pens

Excellent pen; absolutely love writing with it! And the folks at Goulet are terrific; I messed up my order and they were able to fix it before mailing my pen.

I purchased this TWSBI Diamond 580ALR Fountain Pen for my son-in-law to experiment with because TWSBIs are foolproof. They always write, no matter how long they have been inked. TWSBIs are my go-to pens, and I use them daily. A great value for the money.

This is only the 2nd pen I've bought new. I love the weight and ease of use. The ink flows beautifully through the nib.
Highly recommended.

This is only the second fountain pen I've owned. I love the way it writes, and looks.

Lovely color and it writes well. Overall user friendly and shipped in a careful manner.

The pen is awesome!

Though I have a few different models in various colors, I HAD to have this Caribbean color! The TWSBIs write so smooth, they are all a joy to write with!

Given, TWSBI makes great, easy, pens.
This new color is just lovely. Eye catching and pleasant to behold and hold. The nib is particularly delightful.
Yes, you should get yourself one.