Here's my review of the TWSBI 580 Rose Gold. There is a bit copy and paste from my review of the TWSBI Classic, as in most ways the pens are similar.
Appearance + Design
5 / 5
Like all TWSBI fountain pens, this is a lovely, well made pen. The design is well thought out. To be able to fully take it apart and service it, is a bonus. I have a 540, which I love. Then TWSBI released the Rose Gold version of the Mini which I thought was nice, but I preferred the look of black and gold, rather the Mini's white ad gold, so I ended up buying the 580 Rose Gold version. I love the look of the pen. It looks at lot more expensive than it is.
5 / 5
For £60, great value. I haven’t had in long enough to ascertain durability, but it ‘feels’ it will last a long time. The piston moves smoothly and there’s a feeling of quality. It looks and feels more expensive than it is. It’s heavier than my Pelikan M200.
4 / 5
I bought the pen with a Fine nib. It has some flex, which was a nice surprise. This Jowo nib is finer than the than the Bock nib in my 540. The nib was a bit dry to start with. I had used Noodler's Apache Sunset, which looked great in the pen but not so much in the writing. In the ink needs a 'fatter' and wetter nib. I then tried Mont Blanc Limited Edition Daniel Dafoe. Worse. Very Dry. I made some adjustments to the nib, which helped. Next ink was Diamine Sepia. Wow. The pen came alive! It's was now a wettish, smooth nib. The short writing sample in the photos show the shading the ink can give, even with a fine nib. Compared to my 540, the 580 is not there yet, but then I've had the 540 for 2 years longer and had time to 'bed' in. It's early days for the 580.
£60 on a quality piston filler. What’s not to like! My M200 was almost double the price. The TWSBI feels more expensive/substantial.