Does anyone have any experience with this item?  

I am thinking about having my A2 upper modified by Gunsite with this item.  This is the one where they have to remove the carry handle and add the rail mount.

It has real problems, to get it to stay on, since there is no clamping bar you have to chrush the aluminum sides when tightening the socket head screws, It scatches the receiver rail up when trying to get it off.  The sight is so high it doesn't allow anything to go over it like a magnified optic. You best go with an ARMS #38 and have no problems.
Good shootin, Jack

That's a great answer.  You were apparently in such a hurry to bash yet another product  to bother with actually reading the question, but it's a great answer.

cadn24, the A2 setup is a good setup for cowitnessing a dot sight on an A2 upper.  You get all the advantages of the fixed 8/3 sight along with a solid mount for the optic.

Hey hoplite
Truth is not bashing!
If you read the question, maybe you will understand it and the dead nuts factual answer.
However in your case you deserve to have one of those fine rails with the attachment via crushing the metal sides to the reciver.
Jack

Jack, you're obviously having some comprehension issues this evening so I'll type slowly for you.

A.  It's Hoplophile, Hoplite is some other guy.

B.  He asked about the Mark Brown [b]A2[/b] mount.  The one that replaces the carry handle on an A2 upper with a fixed carry handle.  You mill off the carry handle and attach the rail in it's place, leaving the fixed 8/3 rear sight.  While ARMS makes an excellent flip-up rear sight it isn't worth a damn if you don't have a flat-top upper to attach it to.  

If he'd asked about the [b]A3[/b] mount that is a rail and rear sight in one unit which clamps to a flat-top upper then you'd be right on target.  Instead you're just making yourself look like an ass.  Again.

Hoppy
OK, if you insist, it makes even less sense to machine the solid carry handle off, try to get it at the correct ht. and straight, try to secure it to a very limited aluminum receiver so it will never come loose, and pay all the money for that. Then add the cost of the rail/sight, and have something very limited and much more costly that just buying a flat top receiver and stand alone rear sight.
Jack

Thanks for the input guys.

This is going to be done to a CQB only gun that will not have a standard scope ever mounted to it.  If I plan on using a scope for long range, I'll get a new heavy barrel upper unit with a flattop.

And about the cost...It costs $160 total for the part and mounting by a gunsmith at Gunsite.  That's considerably cheaper than buying a flattop upper, a removable sight and paying someone to remount my barrel and other parts to the new upper.

What I need to know is, has anyone used this product and how well does it work or not work?

You're making the installation sound harder than it is, and the total cost is much less than the #38 you suggested.  I don't know what he's being charged for labor but the rail retails at $85 so the total cost is probably less than the cost of a flat-top upper.  While it certainly is less flexible in terms of mounting options it provides a secure mount for dot sights and gives the most durable BUIS on the market.

So long as it's installed correctly, which I'm sure Gunsite can handle, the only potential issue is that the rail will probably be at a slightly different height than a regular flat-top or a flat-top with a riser.  This means that your options for dot sights and mounts will be more limited if you want it to cowitness properly.

Cadn24
You might consider that if you don't alter the A2 receiver with it's built in rear sight, you have somthing that is still marketable and put the money from it's sale to the purchase of a flat top rec. Then you would have a non mongrel set up, and it will be esasier to mount with a bigger selection and be correct for any other scenerious down the road. Put it on the exchange here, a gun show, or ebay, etc., but don't hack up a perfectly good A2 rec. is my basic advise.
Good shootin, Jack