Well I got to run the engine today. 29* and 6'' of snow.
First off this thing starts very easy, one or two flips after it pops when cold are all you need. When warm it usually started first flip w/o choke.
First time starting, it fired right up and idled at a smooth 2000 rpm. I ran three 16oz tanks through it and then played with the needles. I ended up putting them right back to factory settings. The idle was smooth and transition was quick. The BCM muffler isn't all to loud.
As fas as rpm #'s, I'm not as impressed as I had hoped. Though when I spoke to DA on the phone I was told you could lose up to 700 rpm with the BCM muffler. I should gain a few after the engine breaks in. Not too worried but thought I'd get more.
Here's what I got halfway through the third tank.
NX 21X10
6000 rpm
6500 rpm open exhaust
Zinger Pro 22X10
5800 rpm
6400 rpm open exhaust
Time to mount the engine to the plane and fly when the snow melts.

Dave