If you are buying I would try everything I could get my hands on. Revolvers and semi autos both conceal easily. It does take a little more practice to shoot a small revolver accurately, then again small semis take more practice too.
Depends on the weather, your clothing, and lots of other variables. Since it can be carried in any weather, my constant companion is my S&W 442 Centennial Air-weight. From light shorts on a 100 degree day to blue jeans, to snow pants it can be thrown into a pocket in it's Mika pocket holster. Mika makes both round and square bottom pocket holsters and I got one of each to custom fit the pocket I happen to be wearing that day.