No I have never built any MSTR. the reason for the big 1911 styled safety is that I shoot a bit of PPC 1500 and the original Lugersafety is totally impossible to use.
It's by the way an exelent gun for the PPC1500 as its a shooting dicipline that requires very good accuracy.
I am not that good but my maximum so far is 1447 points.
Regards HÃ?Â¥kan
http://www.vapensmedjan.com