Opinions on Nikon Scope base?

Does anyone here have any first hand experience with the Nikon M223 scope base, which has 20 MOA of built in elevation to facilitate long range scope shooting?

Thank you for your constructive advice!

Added (1). ETA: I have looked at the Leupold Mk4 IMS system and the Nikon M223 for mounting a scope on my AR match rifle for 1, 000 yard matches. Unfortunately, being on pension and disability, I have to watch expenditures. The Leupold lists for over $300 once you factor in the base, the rings, and the 20 MOA insert, which via Brownells or Midway can be obtained for about $160 (complete), where as the Nikon base with the built-in 20 MOA can be had for about $100. Once it is "sighted in", it will be on the rifle for (at the moment) no more than 6 matches a year, when iron sights will be used most often. "Quick detachable" is not a priority, just that it not be a major league process requiring a team of gunsmiths to accomplish!

I've used the M223 mount on a Rock River Coyote Carbine that I ordered for a friend from my church. The scope was a Leupold Mark AR 3-9X40mm. I had intended to order the Leupold one-piece mount, but it went out of stock at my distributor, so my account rep recommended the Nikon M223.It was easy to mount, easy to boresight, and rock solid once mounted. The only down side is that it is not a "quick detach" type of set-up, but he was looking for a hunting rifle, so this was not a big deal. I did not get a chance to shoot it after I got it set up for him, but his range report after he shot it was excellent.

I don't think you can go wrong with either the Nikon or Leupold scopes and mounts that are designed specifically for the AR. And mixing the two doesn't seem to hurt either.

I don't really see how you can screw up a chunk of steel. Cheap should be good enough.

I got one with the Nikon M223 from Amazon. It was solid enough and held zero. I don't think the 20MOA is exactly 20, I would say mine is more like 18. For the money, it is a decent mount for an AR. It is ugly, bulky and as mentioned, slow to get on and off. I was very dissapointed with the set up overall, but that is mainly because I had unrealistic expectations of the scope for that price. The mount itself served its function fine for the price.

You might want to get it from Amazon. $70 and free shipping.