Is there a "best practice" for cabin heat/defrost systems for rotary a/c.  Those of you that are flying, how did you approach this item.  It seems to me that with all that heat going out the tailpipe, it is a no-brainer... except for the carbon-monoxide thing.  Then again, I don't want to be scalded with hot ethylene-glycol either.  The exhaust muff seems like the lighter and simpler solution.  On the other hand, with proper ducting, the heater core could add extra cooling during climb-out.

Comments welcome,
Mark S. (hot oil exchanger is out of the question)