I like both. The Kydex is much easier to take on and off for obvious reasons, and offers the option of adjustability. I have a KD holster and 3 Tuckers that use Kydex clips, and on the ones that I take on and off a lot, the clips do eventually get sprung. You can
restore them several times with hot tap water, but they do eventually wear out - usually over a period of many months or a year or more. I've only ever had one break, and only after repeated "restorations".
Since I have several holsters that use them, I keep several extras around - any potential problem solved.
Joe