Did this happen using the screws provided with the RMR (or is it the MOS?) that are short, or the proper screws for using an RMR? I had bought the MOS and RMR then mounted the RDS to slide and thought the included screws were g2g until one fell out during practice. It was then I learned there's a longer screw that needs to be used.
RMR would be preferred but would consider something else that works. As far as the RMS... I like it, but apparently they aren't very rugged.