I think the -PRO mb has USB3.0
I'd definitely invest more and get a Z77 mainboard (doesn't need to be a superboard). What you look at is basically warehouse clearing (badly outdated mb) and you'll be sorry in a few months for that board.
Memory is not a big problem. Anything from 1333mhz to 1866mhz varies by 2-3% in final speed.







