I rarely ever use the rear brakes as I learned in the old MSF days when I was an instructor to use the fronts. Only had a few instances where the additional stopping force of the rear was needed and it wasn't there. Press on the pedal and instant lock up. Fortunately I was able to recover both times before the high side was initiated. I don't need a lecture about braking.
In the 40+ thousand miles since going darkside, I've never had a rear lock up and have had many instances where the additional braking provided by the rear was needed. The bike just stops now, no slide, no drama.
Yes, I consider the Metz a safety hazard and no amount of preaching is going to change that opinion. That's all it is, just my opinion.