Age is just a number. I've met 20 year olds that act 60 and 50 year olds that act like they are 5! I say if everything else feels right about him, go for it!
My Hubby and are are close in age, but before I met him (20 years ago - 15th wedding anniversary this month) I dated a fella that was 12 years older. It didn't work out, but it wasn't because of age... the dude had some serious issues and I wasn't up for the challenge!
Disclaimer: You do have to be at least 18 to be posting here, right? Cuz' if you're only 12 then it just ain't right to date some one 22!