I put in six or so flights today on my 58. The first thing I can say is that my EF Yak finally flies well. It is amazing how much better a plane can fly when it is 2+lbs lighter. Everyone raved about that Yak, and to tell you at 19lbs it is not that good, but get it below 17 and it is a much different plane when it comes to 3D.

First off, I don't baby any of my engines. My break in, is to set the needles to proper running and fly it like you would any other plane. I beat the crap out of it today. Lots of WOT and hoovering, (not that I can hover all that long, maybe 1 minute) not recommend on a new engine, try at your own risk.
I just about have the needles to where I like them. The low will take a few more flights to make perfect, but I am in no hurry because it is really nice where it is anyway.
So, if this engine will last the test of time, (which I have no doubt) It's a winner.
Now it is time to pipe it and have unrealistic power.