I have both & really can't tell much difference in my hand.
But I do prefer the mag release on the G4 as I can reach it w/o re-positioning my grip on the gun; I can't do that with a G3.
As for triggers, I can't say as I ever noticed any difference, but I rework the triggers on all of them so that's a non-issue if there is/was any difference.
I don't really see any differences in normal shooting accuracy either but I've not sandbagged or machine rested them, so I can't really say for sure if there might be some difference if I did shoot them from a good rest.
MM
