Its a great holster, did quite a bit of research looking at comparable Kydex models. It is 100% adjustable by way of the "J" clip attachments. You can also adjust it for depth within your pants, as well as cant. I don't find it shifts at all while walking/sitting. Retention of the pistol is at the front of the trigger guard - very secure and the pistol glides in very smoothly, with a nice sounding and reassuring "click". I've had it since last October, carry daily, and see no harmful wear, just a slight shining on the sides of the front of the trigger guard.
Overall, its extremely comfortable, and normally I carry it at about 4 o'clock which tucks the butt of the pistol very close to the body. I really like the extended body side "sweat shield " which rides the slide where it contacts your body.
I'd rate her at about a 9 out of 10. The only discomfort I've felt is when bending to the side where the pistol is, but I guess no matter what holster you have, it'll dig in ya' a bit if you bend that way.
Workmanship is top notch, and from what I understand, Comp-Tacs customer services is exceptional if you do ever need them.
So, in a nutshell, I don't think I'll be looking for a "better" holster for the P99 - because for me, this is it. The fear of having a certain handgun, and a box full of holsters to go with it, wont happen - I think you'd be very pleased.