i tried one of those BLACKHAWK holsters for a bit.
i really like the idea of it especially since i work in a gun store & often time have my back to customers in a not sooo good area. the police shot & killed 12 people in the county i work in last year. one of our "regular" police friends shot one yesterday.<img src="/ubbthreads/images/graemlins/ooo.gif" alt="" />
i eventually ended up getting rid of it. for me, if i was trying to relly get my gun outta there in a hurry i would'nt always hit the release right on the lever. i'd have to try & "find" the sweet spot. i decided that was'nt to good if i was really needing my gun. maybe i just needed to practice more.

YMMV