I've had two full size and one compact M&P (plus the Shield). I bought the M&Ps when they first came out, and had an issue with them going fully into battery. This is a common compliant online.

Glocks do not have this problem even if you accidentally ride the slide a little during loading.

This "problem" with the M&Ps concerned me greatly and they were quickly sold. All told I probably only fired 500-600 rounds through the three.

Glocks aren't "contemporary" with regards to their ergos, but they are the most thoroughly tested and successful poly design. I trust Glock more than any other except perhaps the HK USP and children.