Mastodawn

@Soblow i've had ok luck with the logitech trackballs, both the m570 and mx ergo. though they don't hold up amazingly under heavy use. i had to take the mx ergo apart to clean the scroll wheel

there's also clones that are a lot cheaper if you just want to try it. i got this one when i accidentally left the mx ergo at my parents' house https://www.amazon.com/dp/B0D2D127J2

i think this style which you use with your right thumb is the most accurate and easiest to adapt to after using a mouse (at least assuming that you're right handed). i've adjusted to this style so well that i even prefer it over a regular mouse for gaming

i also have a kensington orbit trackball mouse which i think is even more ergonomic (you use it with 2-3 fingers) but also a lot less accurate and harder to get used to tho is probably the best if you really want to avoid RSI

personally i'm a huge fan of trackballs no matter the type! i've been using the logitech style ones for like 8 years now and i think it's really helped me to to avoid getting RSI