I love my M&P, but it isn't stock... With even the newest stock trigger, it's only a decent trigger out of the box. Ergos are great though, and it really does feel nice on the hand, near the top of the list in this poll for ergo.
Glocks in Gen 4 version are only so so for me. Ergos don't quite work and the trigger is average at best... I can shoot them decently though regardless.
The Beratta is a nice pistol but a little big for some people. If you are not forced to start in DA mode, it would be less of an issue and it has a good trigger.
The 320 is accurate and is comfortable in the hand. Some people will have issues with the trigger at first due to how it works, and some may hold it in a way that prevents slide lock. It's a soft shooter though.
The P-09 is more comfortable for more people than the Beretta, it would give the M&P a good run for Ergos and likely beat it for most people. Trigger pull is long for some people though, once again, not starting in DA would help. It having the option for cocked and locked make it viable for starting SA. It has the second best stock trigger on the list, behind the Beretta.
I would probably choose the CZ P-09 then.
Put an Apex trigger in the M&P, and my vote would change.