I would definitely carry (and will) the belt loop ones but I will have to see about the clip ons.
I had a clip hopelessly sprung during a scuffle with a druggie one night. My gear went flying luckily only my spare light and a leatherman. I never could repair it. Granted that might be unusual circumstances for some, but it was all too common back in the day.
That was back when they first were in business...but I have been wary of clip on items ever since.
Now my D cell mag loop, that snapped on and stayed put and ended the "discussion", but I did know guys that theirs came unhooked so there you have it....anything can fail under the right (wrong) circumstances.