The Talley Light weight's are what we recommend around here.
The one-piece construction of the Talley Lightweight Aluminum Scope Mount is unique. The rigid design has no joint between the scope and the rifle. The Talley Lightweight unitized design eliminates the possibility of an "out of alignment" interface or "loose connection" between the ring and base of traditional two-piece designs. Ultimately this provides more strength and durability than rival steel rings and bases but doing it with a lighter overall weight. By extruding the 7000 series aluminum known for its durability and then precision CNC machining the mount to its final design Talley can provide you with the strongest, lightest mount system on the market.