I'm currently using an Ibanez RG350DX with Infinity pickups(i think Ibanez' stock pickups). They sound okay but maybe an upgrade will sound better. I'm buying a Peavey Bandit 512 Transtube 80/100 watts (i think thats the name) which might give my tone an upgrade....

I play stuff like:
Paul Gilbert
Racer X
Joe Satriani
Steve Vai
Van Halen

I was thinking of getting Dimarzio PAFs but yeah. maybe theres something better out there? I'm really into playing Paul Gilbert stuff so yeah....
Any suggestions?
Upgrade to a tube amp before you upgrade the pickups. That's gonna make a much bigger impact on your sound, and a solid state just doesn't bring out much difference between pickups.

If you just practice at home, a 5-15W tube amp would do you good.

Oh, and FYI, PAFs are relatively low output pickups. I would look into a set of Breeds for what you play. Or maybe a Breed in the bridge and PAF in the neck.

... yes, I know I just contradicted myself.
Heads will roll. Throats will be slit. Blood will flow like springs of water.
i agree with the user above me. You're better off with a better (possibly tube) amp then the bandit.

edit: messed up the nicks