No data with the ZDZ-80-J model, but with the older ZDZ-80.
As for power, J&A Pitts is a little better than the Supersonic.
Both are a lot better (300-500 rpm) than the Bisson Pitts.
J&A and Supersonic are welded and are more robust construction than the Bisson.
The Bisson appears to be brazed.

The older ZDZ-80 is very sensitive to the muffler. The factory claims the new J model is not as sensitive.