I have been carrying one of my new guns in the BlackHawk Serpa for a couple of months now and have had no problems with it at all. It is smooth and stable in un-holstering and holstering. Once you familiarize yourself with the function of it I don't believe many people will have a problem with it. It would take a small finger to cause the problems in the linked post. And, gravel never gets the opportunity to enter my holsters.
That said, I really do like custom leather holsters much better, but have not been able to get one for the gun I am carrying right now. Once that happens I will continue to use the Serpa for range trips or wet weather.