A current Power Flow Exhaust Systems interest list (Excel spreadsheet) has been updated to version 2004003 including the recent additions.I have been after them for going on three years now, for the Sierra. I am only a 15 minute flight from them, and have offered my plane as a test bed. We formed this list in an effort to demonstrate that there is a serious market in our group of aircraft.
I will be approaching them again in October for status, and the possibility of providing a “test bed” aircraft. Please let me know if you would like to be added to the list (and please provide all the info requested on the list). Note that they will not yet consider the Duchess or Skipper due to the very small number of airframes built, unless some number of 76 and 77 owners band together, and are willing to commit by means of deposits. If enough people are willing to commit the same way for the 19/23/24, we might get faster action on them too.