I have been using the Serpa Level III with the Xiphos light holster with my Glock 22 as my duty rig for the past year. That light is an awesome light, but that would be for another thread!!
I do not see how anyone can have a ND with this setup with the blame resting solely on the design of the holster. My only complaint was that the holster rode so low compared to my old Safariland level 2 holster. But, now I am used to this holster and can appreciate this lower ride height in that it gives me a faster draw. I personally find the draw easier and faster than any other Level 3 holster that I have tried. And my finger is always where it should be, resting along the slide just above the trigger!! Even when I first started using this holster, I never have had my finger within the trigger guard, I repeat NEVER! And I for one find it extremely hard to believe the tales I have heard about ND's and such. I think this is all operator error, whether they are a Delta Force commando or a mall security guard it is still error on the part of the user!
As far as the reports of rocks or debris being caught in the mechanism and rendering the holster inoperable, all I can say is that from what I have read thus far on the net, is that all these different posters always "know" someone that this is happened to yet I never came across an individual that actually had this happen to themselves. Makes me wonder???
Any holster can have a malfunction, I can remember a time or two in freezing temps and having my metal snap on my Safariland "stick" or "freeze" if you will requiring me to yank the hell out of it just to unsnap it. I just put a small dab of vaseline on the button and I was good to go!
We also utilize the Serpa Taser holsters for our X26's. During one incident I watched my partner's get ripped off his duty belt as we fought with a suspect. He was up against a 4 foot chain link fence and his holster got caught in the fencing, broke the clips/loops and the holster and taser skidded across the sidewalk still secured with the holster!
So, nothing is indestructible! On a side note, BlackHawk sent him a replacement with no questions asked.
Basically, don't base your decision on opinions from others on a particular brand, style, material and/or etc on what others say and no matter what holster you choose, you should try it out and practice with it whether it be for duty or CCW use, after all its your ass on the line and maybe someone else's.
TO each his own. Be safe!