One-shot wonder (very disappointing!) - Swampfox Kingslayer 1x22mm Micro Reflex Red Dot Sight

I really wanted to like this thing- I like the overall look, and I like the reticle, but (story of my life) looks deceive! So here is my sad story. I had this mounted to the slide of an XDS 45. All mounting was done by the book, and I even took measurements prior to shooting because I wanted to be able to determine if there was any physical movement of the sight after firing. I sighted in with a laser bore sighter and took it to the range. First shot was right on, which in theory it should have been. Second shot was not on the target! It was so far off I had to re-sight back in, which was then impossible because the adjustment ran out of travel! I shot it anyways to see what would happen, because I wanted to see if it would 'settle in'. It didn't. It was totally random, and after a few more shots it was so far off I could not even come close to sighting it back in. I took it home and measured the position of the sight on the slide, and it had not moved at all, which leads me to believe that whatever bad was happening was internal to the device.
Granted, it was a hard task I asked from it, I agree. That little 45 slide bangs like you would not believe, but I certainly expected much more! There are many guys out there mounting red dots on XDS, including the 45 model with great success. So my advice would be to only mount this thing to something with very little recoil, which really defeats the purpose in my opinion.