I've been running my M&P15 for about a year and its been absolutely flawless. I have started to take closer notice to the craftmanship of the fit. Maybe it's just mine, but there is noticeable wiggle at the foward pin of the lower receiver. Also, I still have the original sliding stock installed which isn't a tight finish. The final thing I've noticed is the angle beneath the trigger guard where the grip meets... it's close to a right angle and I wish there was more curvature. After several mags, my "finger" finger starts to hurt because of the upward pressure I place at that point. Are there any fixes for these little nuances? I assume that the wiggle from the pin and stock could affect the accuracy. If anyone has noticed the same things and corrected them, please let me know what you did. Thanks

Get a CTR stock. It has a friction lever that tightens up the slop in the stock (my MOE stock did the same thing, but it wasn't too god-awful bad).

As to the trigger guard, you might want to look into getting replacing it with one of the many bent trigger guards available.

Some (like Magpul's) have a kink in them to allow the use of winter gloves. This gives your finger more room.

There are other guards available that are actually rounded, something like a revolver.

Finally, you can get pistol grips that have an integrated trigger guard (I don't particularly care for these, though).

As jsimmons points out, there are quite a few aftermarket trigger guards that fill the hole behind the trigger (hole is needed I think so that the stock trigger guard can flip down, most aftermarket do not flip down, so can fill that space). There's also a little block someone makes to fill in that gap, but I can't find that now.

I tried the MagPul aluminum trigger guard. It is very nicely made, installs easy, and feels and works great. I, ah, well, I, hate to admit it, but I've gone back to the stock guard; the MagPul just changed the look I love too much (sad but true, does that make my AR a "man-Barbie" because I've changed it back just for looks?).

I was a little disappointed in the amount of upper to lower play my M&P15OR has, so I got an Acuwedge (spelling>?). Works pretty good.

The stock has a bit too much play for me also. It so loose it seems like maybe it's a commercial stock on a Mil-spec tube (I know S&W uses the Mil-spec tube). I really like the MagPul CTR stock, as it has the friction lock (and I like the way it looks). At around $90, it seems kind of expensive, and I must get an EOTech XPS2-0 first. I must