I have the gen 4 on the way. Ive done lots of research. The 30s has the same grip as the sf or gen 4 and it has the 36 slide. I hear its great. Only thing is it has a little more recoil than the other 30's. They say its no big deal tho. Nothing to worry about.
By the way. Im super pumped about my G30 gen 4. Any day now.