I've got both, a M627PC 5" from the original batch, and a M686-5 Plus 4". If I had to choose between them, it would be extremely difficult. The M686+ is probably more useful in a variety of roles (being an L-frame), has a terrific trigger, seven rounds, and the satin stainless finish is very tough. On the other hand, the M627PC is a wonder. Great trigger, eight rounds on tap, and the heavier N-frame handles recoil with ease. It doesn't hurt that it's also a good looking beast.

Oh, there's one interesting difference. The smaller M686+ has a longer cylinder that can handle Remington 180gr SJHP bullets seated to the cannelure, while the larger M627PC has a shorter cylinder and can't load the same round without the bullet projecting beyond the front of the cylinder. Weird but true...