I have one on a composite stalker 7mm-08. The idea is sound and it certainly does work. In my opinion it was marketed to make the buyer be able to get factory ammo to shoot itty bitty groups. The reality is that while possible with factory ammo, many people do not buy enough ammo to really take advantage of that. You can initially set it and then start to tweak it. This will require a fair amount of ammo to find the best setting for a particular gun and load. The issue is when you run out of that ammo and head to the store to buy more you may not get the exact same lot number and you may have to start over with the tuning and waste mote time and ammo. If you reload just pick a bullet and velocity you want to be at then tune for that load. As long as you have the components to load more exactly the same you are good to go. If I had to do it over again I probably would not buy my rifle with the BOSS. It is generally easy enough to find an accurate load and the BOSS does add some length and weight to an otherwise really handy rifle.
