I don't know much about QD mount systems, but I don't think they are a great solution for dedicated long range rifles.
Once you start setting up a rifle to shoot the distances you seem to intend, the mounting of the scope and it's alignment to the barrel and leveling of its reticle can get critical. Once you have all of that setup for one rifle and then move the scope to another long range rifle, and back and forth, it may be impossible to duplicate those settings. This is because the scope itself may have to be realigned in the rings each time because the rails, on each scope, and their alignment to the barrels, will probably be different enough to cause issues with how level the reticle is, etc.
Also, if you to have to move the scope in the rings, future scope slippage might happen, or any number of other things. These small changes can cause havoc with long range accuracy and it will be hard to diagnose. You might find yourself wasting a lot of bullets an barrel life at the range just trying to diagnose and get things working the same after moving the scope.
If I were building a pair of long range rifles for target and hunting. I would work a budget so there would be two dedicated scopes as well.
Just some thoughts.