I have both guns - plus a Glock 19 - and a caliper, but :banghead: no camera.
The M&P is considerably shorter in the butt than the PCR. (I could not measure this accurately with the caliper, but the difference is obvious, at least an inch.) The width of the grips at their widest point is also slimmer (M&P with medium backstrap 1.260 inches, PCR with slim wood grips 1.400 inches). The M&P's
slide is considerably wider than that of the PCR (1.085 inches vs. a very slender 0.935 inch; its frame is actually wider than the slide). And the Glock 19's slide is 1.010 inches, far from the 1.4 you mentioned.
Which one do I like better? I'm still trying to decide.
Subjectively, the slimmer PCR is more comfortable to carry IWB and has a less "top-heavy" balance. But the M&P has the same trigger pull for each shot vs. the PCR's DA/SA transition (it cannot be carried cocked and locked). Also, my personal M&P has had
100% perfect functioning from round one, while the PCR has exhibited some ammo sensitivity.