I always reset the knobs to zero. If using comeups for longer range shooting, sure makes it a lot easier for return to zero. I've never seen a tgt. turret that wouldn't allow the turret housing to reset to zero.
I've never had an exposed turret move on me, altho. i did lose a Burris turret housing itself once several years ago. Since then i drill one more hole for the turret housing screw in the Burris's, as they only come with 2 little ones, and that's not enuf, IMO.
U have to be careful with Burris turrets, I've seen the turret housing screws slip on the shaft with fast twisting, and that's not a lot of fun. When u seat the Burris turrets try to get the screws to seat into the indent of the shaft--it's possible to tighten them on the upper rounded part, and that's a problem waiting to happen.