I am a Leupold fan so that is my vote. I have had nothing but good to report about them. Including the scope I sent in to be fixed. Bought it at a garage sale for $10, dented bell, a deep scratch running up to it, and a loose reticle. Clearly abuse. But it was still fixed for free and returned less then two weeks later.
On the other hand I have never had a bad experience with Burris either. I also never owned one. I am sure that they are great though, and who knows if I would have bought a burris before I bought a Leupold I could be a burris man. But of the 19 Rifles I own with scopes, 18 are Leupolds, ranging from the VX-1 to the Mark IV LR/T