I bought a rifle for my father that had a Swift 4-12x40Ao on it. I hated the thing, but he loves it. We threw it on light duty on his 22, but it functioned perfectly on his 3006, during the time it was mounted there.
HOWEVER, the one gripe I have is that ALL of the adjuctable threads (AO, focus, power ring) ALL STICK and are heavy to turn. I was tempted to get the old oil out with a bit of WD40, but figured the WD40 might get inside the scope.
Other than that, they're nice for range work, but I wouldn't trust their durability outside of that.