This seems to be Safariland's answer to the much-touted Blackhawk SERPA, and I personally prefer this to the SERPA: the thumb release system not only lessens the chance of an accidental discharge, but you can also disengage the safety of a 1911 in the same motion. Plus it's made by Safariland.
Pros: Holds securely, won't damage finish, can mod for different mounting options, Safariland
Cons: Hard to clean inside if sand gets in it
This review was written in the old system and had content requirements that are different than reviews written today.