I have 3 and use all 3 from time to time. They are all made for the full size M&P but the compact works just fine with all 3. The one I like the most is a Fobus evolution paddle. It has no retention, just friction to keep the gun in place. It works good. I have read postings that it will rub the finish off. I haven't noticed that yet. The second one is a Blackhawk CQS serpa. Its a retention holster. The gun won't come out until you press the reliece. It could be the best choice in crowded areas. The fobus rides close and feels better. You can forget its on your hip. The blackhawk may show more through a shirt. My third one is a cheap inside the pants. It works, but I can"t use it for very long. What I usually do is put my M&P40c in my pants pocket. Most of my pants are cargo pants with extra pockets. The pockets help hide the gun.
Midway has holsters listed by gun and they are rated by us users. If we don't like one we let them know it.
Good luck
Phil