The Cframe is concealable with ease.
If you have large hands like me, shooting a compact grip becomes tiresome or unwieldy.
The shorter barrel makes for easier and faster draw.
If you carry properly in a properly canted holster, outside or inside the waist band, a full size fire arm is easily concealable.
Personal opinions and impressions.I think his point is that if you want a full grip get the M-A1. The lost barrel length doesn't provide more concealment and gives you a smaller sight radius.