When I had the older tires (forget the brand but they were provided with the kit), I could not lock them up although I did leave 300 ft of rubber from an aborted take off.  I now have the Michelins and had not been able to leave rubber from hard braking (don't know what that says but that was before the new rotor)  Now, I have not tried to leave rubber with the new rotor, but they do appear to maintain steady braking action even when heated - the old ones would fade at that point.    I suspect that if you have a tail dragger, it might be best to stay with Van's stock - as you don't want to end up on your nose.  But, with a training wheel up front, you can reallllllyyyyy get on the binders hard without worry.

 

The new high energy brakes get their 40% greater stopping power apparently from the thicker rotor dissipating the heat from the pads better and less warping and wobbling of the rotor plate under pressure.

 

ED