The main thing to know about these thumbsticks is that, well, they don't have rubber grips. So there's obviously less friction between your thumb and the stick. This means your thumb is more easily able to slip off when jerking the stick all the way in any direction.
For me, the oil and sweat that my hands naturally produce during a play session will act as a lubricant of sorts, impeding me from being able to make those super-fine motions I'm accustomed to with a rubber thumbstick.
Other than that, I've got nothing but pros. They're easy to install, fit well on my GC controller stickboxes, and so far look like the best long-term solution for someone who has tried, and despised, so many garbage thumbsticks off eBay/AliExpress whose plastic feels cheaper than a ketchup packet at a restaurant (free).
