Which is best? I've always been comfortable with R, but I see a several players in the community using A. What are the advantage of shoulder buttons vs. A, and which would you guys recommend using? Thanks!

(I'm mrmario5500 as well btw)

We all mostly use a because you can push it quicker than L or R and when using the rocket star specifically, you have to mash your brake a lot. So I reccomend using A but if you can get good results using L or R, go for it :)

For the most part, I've actually been doing R for charges and A for everything else (mashing while turning, buttons, etc). It seems to be working out pretty well.