The stock floorplate on the G30 magazine ALWAYS pinches my little finger. Changed to Pearce floorplates...problem solved.
The G36 stock floorplate NEVER pinches my finger. Dunno why, but it never happens. It's just as well, since Pearce Grip doesn't make a standard replacement floorplate for the G36, just their "+1" floorplate, which works fine, doesn't pinch, but protrudes lower than the stock item. Not much of a problem, but I carry one on my spare mag more than on the in-gun mag, just to enhance concealability.
While the numeric measurement differences between the G30 and G36 sound trivial, the G36 FEELS much more comfortable in the hand to me, since the G36 grip approximates that of the 1911 much more closely than any other Glock, and the thinner G36 is SIGNIFICANTLY lighter and "flatter" feeling than the G30 when carried in a holster, especially an IWB holster.
I've carried and shot G30s and 1911s for years, but I gotta give credit to the G36 as a CCW gun; if you're commited to the .45ACP, you get 6 rounds in the mag with one in the chamber in a package weighing just under 28 oz, while the very same capacity (6 plus 1) in a compact 1911 design like my Les Baer Stinger is about 40oz!
Again, some might say that a 12 oz weight difference isn't much, but it feels like a BIG difference to me, especially when carrying all day.
The G36 has somewhat more "felt recoil" than the G30, not surprisingly, but it's no problem. Much more surprising to me is how close the "felt recoil" of the 28 oz. G36 is to that of the 40 oz. Stinger!
I like my G36. There are quite a few vocal G30 owners who are highly critical of the G36 over at Glock Talk (they don't own one, of course), but I find it an excellent gun for CCW, and better in this role than the G30, IMNSHO, due to its compactness and lighter weight.
Best.