I've been using them for a while now. I don't even bother breaking in brushes after I run the shaper on them. Just cut the motor, use the shaper on the new brushes, assemble the motor and run. I have been seeing less comm wear, longer brush life and more consistent performance using the shapers.
I haven't tried the new serator shapers yet but they look awesome for stock racing.
I was stunned when they offered to send us early adopters with updated tools for free. When was the last time you saw an RC company do that?
Team Kyosho, Orion, KO Propo America, Avid RC