i went with cz custom on my s2, i liked the idea of having different optic options with their plate system. i have a friend that uses an sp01 shadow with a dovetail mount and is happy with his set up.
that must be a pretty extreme angle to be missing at 20yrds. If you are say shooting at a 45 deg angle at a range of 20 yrds your angle corrected range at that angle would be 14.14yrds.
the few ets mags i had would work great until they got some dirt inside then they would jam up. sent them back to ets who replaced them then i sold them.