So I just purchased an M&P Compact 9mm w/ manual safety and, after just one range trip it has taken the primary spot over my XD subcompact as my EDC. The trigger, the recoil, the weight, the footprint, it all makes for a more accurate and easier to conceal pistol than the XD. I really appreciate the ambi thumb safety on this thing too. And I really love my workhorse XD so my expectations were very high and the M&P exceded them. Today at the range the M&P was fed 200 rounds of a combination of Winchester white box FMJ and Blazer FMJ without a single malfunction. I also cleaned the gun meticulously before taking it to the range. What impressed me the most about this pistol is the trigger. It's smooth and doesn't have very much pretravel, unlike the XD which has quite a bit of travel. The reset on the M&P isn't as crisp as as the XD but all the other factors compensate for this. I also shot equally well with both the flush mag and the pinky extension mag, which was motivating. Even though the ext mag felt more comfortable, I will probably carry with the flush mag for that extra little bit of concealment.
The trigger brings me to something else. When I bought the gun, they had the display model and one NIB. I asked for the NIB model. While the salesman was getting the paperwork ready I took the NIB gun out and was feeling it out. I cocked it and dry fired it. I was shocked. The triggers on the display and NIB models were like night and day. The NIB trigger was extremely gritty and had a really long pull. Just to make sure I wasn't imagining things I had the clerk dry fire it, who then showed this to the manager. After feeling the differences for himself, the manager's exact words were "Well this ones going back to Smith. There's no way I would sell this gun to somebody." Needless to say, I left happily with the display pistol.
I suppose this sort of thing can transcend all gun types and manufacturers, but I felt my experience was compelling enough to share with you guys, especially if you're considering this gun. I also haven't purchased a whole lot of guns in my lifetime so take it with a grain of salt.
Here are some comparison pics for you guys. You can see that when it comes to the thickness, the XD and M&P are nearly identical. Although the M&P is longer, it's quite a bit shorter than the XD, which will hopefully make for less printing.