Out of the box, it fits on my a-5 perfect... everyone say's that it doesn't mount on the 3/8" dovetail, and their right; however, it does fit around the body of the a-5 mount. I was a little upset at first that I couldn't mount it, but then I opened the screws all the way and it mounts perfect around the sight rail (outside part). People should experiment before coming to conclusions... :)
I took off the a-5 rotator site on the back and slide the site all the way to the rear of the gun and the hopper just misses front lense. This allows me to take the hopper off properly if need be.
The only weakness I see with the site is the laser adjustment. I wanted to adjust it for farther distances and it is a precison adjustment for rifles.
I like it! I give it a 9 because of the adjustment