Hi!!! Im new but have been trying to keep up with all the new info, so take it easy on me.

Im trying to paint my wheels and a toyota corolla but im still in the lookout for my first spray gun. Here are what I have so far
Finishline 3 (13cfm)
TCPglobal kit (<8cfm)
Sharpe FX300 (9.5cfm)
Bink BHV (13cfm)
my compressor 9.1scfm @ 40psi BUT I can rent a better one (thats what im planning to do).
I dont know what makes one better than the other! Is it the cfm? More cfm required the better? PLease some advice on this guns and what other you guys recommend!!
Thanks!!