TWSBI Diamond 580 vs TWSBI ECO Black

a Diplomat Aero. This one is *hefty*; it was one of my first heavier pens and I love the way it feels in hand.

I really really enjoy writing with this pen. I got a Pilot Metropolitan last year so when I initially picked this one up, I was a little put off by how light it felt in comparison. but after a few weeks of using it I'm super happy with the weight difference - this one really glides across the page (in a Clairefontaine notebook) and it's really nice to be able to switch between a lighter pen and a weightier one. it is also of course very cool & useful to see how much ink is left in the pen

Additionally, the ink capacity on the Kaweco has never been a problem for me, as it always got me through at least a whole day of college notes with the EF nib.

Personally, I like the TWSBI eco for its large ink capacity and comfort. It has a good weight to it and there are beautiful colors! :)

The price for such a good fountain pen is unreal. Pens of similar writing quality made in Germany, Italy, or Japan cost 2 and 3 times as much.

It uses cartridges, but doesn’t come with a converter. The TWSBI Eco is a great pen that may be more than you are thinking of spending ($30) but is a really nice pen that could be a buy it once and done. It is only bottle fill, and that adds about $10 for ink, but the pen is great and hold a lot of ink. Depending on your use this can be a factor

5 ultraflex in TWSBI 580 and it just didn't work - the inkflow wasn't there. Every #6 nib I placed into PenBBS struggled to function (and taking out the feed each time was a literal pain I do not want to repeat again). I bought Lamy nibs by mistake and don't even want to start down the Lamy road, so I'm leaving those untouched. I still love all the pens I have, but for future purchases, I think I'll stick strictly to the pens that take #5 or #6 Jowo nibs without much of a struggle in the feed

Now writing with this pen is where I have my problems. I compared it to the Lamy Safari and Metropolitan Pilot which are both cheaper than the TWSBI ECO and both write several orders of magnitude smoother than the TWSBI ECO. This pen is incredibly scratchy and this was directly comparing to the other 2 pens with 2 different inks. Carbon Ink Black and Waterman Serenity Blue