I've got a SWFA SS for a RRA varmint that has Picatinny atop the receiver. I'm not getting the RRA mount because I feel its height is a little high. I'm looking for something lower than 1.5 height. I'd like to keep it about a 100 dollars or lower. I was thinking of the Nikon XRD, but it says it fits weaver and picatinny. It seems to me the best mount would be a Picatinny mount only, being I've got a Picatinny rail. Am I right? I'd think a weaver mount would be more likely to move or something. The SWFA has a descent looking mount that's Picatinny, but the coupler piece w/ the two horizontal screws is an inch shorter than rock rivers which is 3.75 " A lot of the cantilever mounts say they have a two inch offset. What or where to where is the offset measure from? Is it the back side of the front ring to that clamping coupler below? Also some mounts say they have a 20 moa. I know what moa means, but don't understand what it has to do w/ the mount? Seems I've been to several websites for mounts. I find it surprising how many don't list dimensions or even the scope height. If any of you can please answer any of these questions or recommend a cantilever mount, or any other advice, it would be appreciated.