A note: POM wears at molds much faster than PBT. I personally prefer POM even so, and I think most people will agree.
Besides that, I recommend you prototype the design a little further. Most cylindrical profiles either have a narrower top than bottom or a slight angle to be more comfortable.
Both features are absent here. Cherry's ML keycaps are a good example of how best this can be done.
Signature Plastics also has two low profile keycap families designed for ML that have some dimensions you could use for reference.
TLDR; flat sides and zero degree angled tops make for a very unexceptional keycap.
edit: my bad. there's a slight angle on the sides. Frankly, not enough. Needs the inclined top as well.
We designed this keycap specifically for our keyboard, and in fact we have tested many different designs, including some that are taller. At the end, this design is chosen for a number of reasons:
1. It is the most comfortable design out of the many we have tested. Personally I think eyeballing a keycap design from photos and coming to a conclusion on the comfort level is difficult.
2. The keycap is designed specifically for maximizing low-profile. Generally it simply does not make sense to pay a premium price for choc switches to have tall keycaps. As such the height of the keycap is an absolutely critical constraint. With a low height, the constraints on the design is much more stringent. There is only so much sloping one can do.
3. This keycap is specifically designed to be visually compatible with MBK key profile. Many people uses MBK key profile for Choc keyboards. I like MBK too, however sometimes and some boards do need a cylindrical profile for comfort and ergonomics for certain keys. For example, I personally think for many keebs the thumb keys are more comfortable with a cylindrical profile than a dish profile.
4. As for inclined top, it is an option we have explored quite a bit. We tried quite a few inclination angles. But at the end we decided that a cylinder with 0 degree profile is the most comfortable for our keyboard.
P.S. it definitely is not a flat side if you look carefully. The sides are composed of two (non 90-degrees) surfaces and a small curved transition area.
