I haven't had the chance to try the Apex sear in a M&P yet, although I know someone who has and has spoken very highly of how it worked for him. I know a couple of guys who are going to order the sears, so I suppose I'll have the chance to test-fire a M&P with the aftermarket sear at some point and see how it does.
In the meantime, my M&P 45 and 40c have satisfactory triggers for my needs (defensive carry retirement CCW weapons), although they didn't exactly start out that way. Both were heavy and had some varying degrees of roughness at first. I remember my M&P 45 gave me some averaged trigger pull readings on my digital gauge running from 8 1/2 - 9+ lbs when I checked it a couple of times when it was new. Considering the expected +/- 2 lbs tolerance regarding the 7 lb trigger pull weight for the .45, mine obviously came in on the heavy end.
The weight and minor roughness didn't prevent it from having a consistently predictable break and nice trigger recovery, and it exhibited some excellent accuracy from the very first magazine load fired, but it was heavier than I'd hoped. I just had to work harder in the beginning, but that was the familiarization period with a new design/model, anyway.
By the time I'd ran about 2,500+ rounds through it I realized it had become a lot smoother and seemingly lighter, so I checked it on the gauge again. I got a couple averaged group readings of 5 1/2 - 6 lbs. Nice. I didn't use the trigger weights I keep for checking revolvers, but the digital gauge was close enough for what I wanted to know. That's the weight I prefer in my 'working' 1911's and other pistols (unless the first shot is a heavy DA trigger stroke in a TDA gun, of course).
I tried a 2010 production M&P 45c a while back and my impression was that the trigger was smoother and lighter right out of the box than mine had been. Not as light and smooth as mine has become, but better than mine was when NIB.
I'm not interested in competitive shooting, though. If I were, I'd consider the PC package and sear, or maybe the Apex sear. Dunno. Maybe a Pro Series, if they were to ever offer one in .45 ACP.