I just bought a guitar with a top mount Floyd Rose and I know it’s mostly dive only which is fine. Is there any difference in the setup and tuning etc. that’s different from the typical recessed guitars?
Depends. You can still "float" a top mount or you can crank the springs down and have it rest on the body.
If you want to be able to pull up you should float it. Setup and tuning will be the same as a recessed bridge. Otherwise, setup is almost as easy as a fixed bridge. EVH always let his bridges rest on the body because it was supposed to be more resonant.
Yup, Floyd's were floaters long before someone decided to claw the back out to recess them. All it really affects is how high the bridge and fretboard sit off the top of the body, which is a feel thing for some players.