Hey man, if you're into Dream Theater and shred, definitely go for the Air Norton 7 in the neck. I've got one in my RG1527 and it's absolutely amazing--smooth creamy leads, lush cleans, and you can even use it for rhythm if you're too lazy to constantly switch pick-ups (although I don't recommend that).
I've got a Blaze Custom in the
bridge position, and I'm happy with that, but I don't have much to compare it to. You might want to try Petrucci's D-Sonic 7 pick-up, I've heard really good things about it.