Any experience with these (inexpensive) Sure Grip units?

Spendy, but I paid $572 for this in 2021 for my 8.75. One of the local drivetrain specialists recommended it to me. He told me to avoid buying the cheap Ebay junk, he's been in business over 30 years and also builds racing units, so I took his advice.
Auburn Gear Inc 546051 Auburn Gear Grip-N-Loc Differentials | Summit Racing

The Richmond 3.55 10 spline ring & pinion I bought was $271 back then as well.