M&P Apex triggers are great!
Do they improve accuracy? No.
In my opinion/experience:
Apex triggers are much better than the old 1.0 triggers
Apex triggers are a better than the 1.0 PC triggers
Apex triggers are slightly better than the 2.0 triggers
Apex triggers are slightly better than the 2.0 PC triggers
When 1.0 was all we had, I put Apex triggers in them. Since the 2.0 came out, the slight improvement doesn't seem worth the cost to me.
That said, competition shooters may find the slight improvement worth it.
And those who just like tinkering will tinker no matter what. So, tinker away...
Note: When I say "Apex trigger", I mean the full trigger kit. As for what I call the trigger shoe, that's completely a matter of feel. I really like the new 2.0 trigger shoe but don't care for the old hinged trigger, though I still have it on several old 2.0s.