Have a LaRue OBR on order and am researching the optics while I wait. Probably going to go with something like a Vortex Razor HD 6-24x if the budget allows, otherwise might default to a Mark 4, anyway a 50mm objective. Ay question is can I use two piece rings, like the badger ordnance extra high and still have room (enough rail length) to mount the scope on the upper? I don't really want or need QD so I'd prefer just to use simple rings. Also the OBR has a 20 MOA cant built into the top rail. According to some online calculators anyting that mounts the optic centerline at or above 1.25" will clear the rail with a 50mm objective, but I'm not sure exactly what height works best for cheek weld on the OBR/AR-10 pattern rifle. It seems like most people that get an OBR just use larue mounts, but they're all "QD" and I don't want that, just want something as solid as possible with the least possibility of wandering zero. I do shoot NTCH on AR-15's but have heard the geometry is different on the AR-10, so don't know if I'd do it there. Any help is appreciated.