I had a Dynon shear screw fail about a year and a half ago or so, on the SV-32 pitch servo in my RV-8.
Per Dynon, they adopted a stronger shear screw beginning late in the 1st quarter of 2017. It was adopted due to premature fatigue failures of the previous spec'd screw during normal use.
I called Dynon after verifying the shear screw had failed and they quickly sent replacement shear screw kits gratis (including one for the roll servo for if/when it fails). The kit includes the shear screw, an Allen wrench, a cotter pin, thread locker, and instructions for replacement.
Search "shear screw" in the Forums and you will find a few threads on the subject.