Question....if you like them well broken in, what do you do when you install a new one? Obviously an adjustment period is needed. I used to use the LePro and because of this and quit using it.
New plain Elkmaster break in>>>sit out on the patio and using a loose closed bridge wedged against your thigh, imitate the 'dart' stroke a couple hundred times.
Requires a straight medium speed vertical stroke, allowing for the 'bounce' since you let go of the shaft. Do a little shaping if needed along the way.
Oh....smooth finished concrete is preferred over the rough finish concrete.

Note: if you break a ferrule....you're hitting it too hard.