For those looking for inexpensive solid mounts for an AR -- look into the Dura Sight See Thru mounts for Muzzle Loaders. Go to "www.durasight.com". I have purchased a couple sets of these to mount 1 inch scopes on a SW MP15-22, my son's 6.8 and my 223 upper. I bought them for under $30.00 for the set at cabelas. If they are good enough for a hard kicking MZ with a 150 grain charge, they will work on a 450B. While not quite QD, setup right they will slide off after removing the cross bolt screw.
i like them because of the large square hole in the ring under the scope, so I can mount my laser max on the rail and shine thru the hole. Plus, I can use the scope as a carry handle. I could not do that with the Burris PER mounts.
The height of the rings is exactly the same as the standard ultra high or extra high tacticle mounts at 1/3 the price.