This is the third DNZ mount I've purchased; the second for a Contender barrel. All one piece makes for a very 'tidy' installation, and no need to lap the rings for alignment. The rear ring ends 3/16" past the barrel breech, which doesn't sound like it would make much of a difference, but it does. Gives much more adjustment for better eye relief. This is why I bought the second one for a Contender barrel. The only downfall is that they don't make a "low" version for smaller objective scopes. A 32mm objective sits 1/4" above the barrel.
Pros: Clean, Tight, Extra Offset, One-Piece
Cons: Height, Cost
This review was written in the old system and had content requirements that are different than reviews written today.