It's not just the weight, but also the width. That extra quarter? eighth? of an inch can make a -big- difference in how the pistol rides in certain concealment holster types, how it interacts with clothing, and how it interacts with the hand. I have a G42, and am looking for a G43. I have, or have shot, Mustang/P238s (same gun, really), LCP/P3ATs, and several other "pocket pistols" in .380, and the G42 is, to my hands, far easier in recoil and far easier to shoot accurately than any other pocket pistol I've tried (can't believe I just said that about a Bloc... er, Glock
). What it is definitely not, is a "combat pistol." It -is- a deep-concealment firearm, intended as a "gun you have when you can't have a real gun," and for that role, it performs admirably, I think. Yeah, it gives up significant firepower compared to its fatter bretheren, but it's intended for a slightly different role, one which the 26/27 can fill, but nowhere nearly as well.
Oh, and yes, I am intending another 9mm Glock after the 43, probably a 19. I've finally given in and admitted they do shoot well, even for me, and I'm becoming less and less willing to carry a prize favorite gun that is not so easily replaced.