He can make pretty much whatever shape you want. The big ones are really surprisingly comfortable. Depends what you play.
These picks are really expensive, they are equivalent of custom shop guitars which are made for collectors. I personally don't use them day by day, but they are just fun to have
I'm sure that there are a lot of great picks out there, but the problem ist the testing. I'm owning expensive vintage guitars ('54 Telecaster, '58 Stratocaster and more), but I could play them for hours (or days) before I spent the money. I've never seen the Swiss picks in any music-stores, how shall I test them and find the right one?
That's the main problem, boutique-picks are hard to find and there's hardly a chance to test them.