+1 on the Streamlight TLR-4
It's got a real nice fit on the M&P Compact. I picked mine up at a local gunshop for $130 out the door. Good quality made product. I have shot about 300 rounds with the laser and light on. No problems of any kind. Its just a wee bit big compared to the $300 Viridian brand lights.
Once I got the laser dialed in, I was really impressed with the accuracy. The 110 lumen light is good out to about 60ft. I tried it outside on a dark night...it's like a small police helicopter spotlight. More than adequate for home defense.