RRA mount puts the occular lense higher than standard irons (1.4") by about .25", but at $55 is less expensive than a Larue ($140). I went with a used Armalite one piece mount ($60 used on EE, $87 new), and I'm very happy with it. It puts the scope at the same height as stock irons (or maybe even a hair lower) but it's solid. I didn't like how high my scope was with the RRA one-piece mount, so check your cheek weld on a borrowed rifle with one before you buy if possible.
Brian