Choice between lever lock or theaded bolt? Which did you choose? Why? Would you do it again or switch to the other?

Lever lock. The QD's come with the bolt but I like having the lever because I have a talley peep as a backup on the rifle.

If I had a rifle with no open sights but wanted a second scope, I'd probably just use the bolts and keep a few spare wrenches around. I suppose you could argue that levers would make sense here, but we don't necessarily have to make sense with our opinions.

I have Talley LW's on my 270 that I just got and I like them, but the anal- retentive-obsessive-screw-tightener in me hates the fact I can't lay a torx wrench on each screw when I quadruple-check everything.

I have had both, and for my use, I prefer the screw locks. Smoother profile and less to catch/wear on clothing etc.

My application is so that I can travel with a spare sighted in scope. I always carry two keys - one for scope rings/mounts, and one for guard screws.

The levers are good for removing a scope in the field if access to open sights may be required. Mucking around with the screw locks would not be practicable in these situations

Use whichever suits your application.

I have both. while all my hunting rifles have open sights for emergency backup. I have yet to use them. The optics and mounting systems built today are extremely reliable. If I had to do it all over again I would save a lot of money by eliminating all open sights all together. I don't like levers that could be loosened or unlocked unintentionally at the worst time in whatever field conditions/thick brush etc... and peace of mind is worth something. I prefer a quality solid fixed bolt system and for back up an extra light weight scope such as the Leupold 2.5x with rings and appropriate mounting allen wrench.