We are doing our first right now and are about 14 hours in and should have it wrapped up in 6 to 8 hours more as all the wiring is done and the servo brackets are in place and drilled. Just need to bolt brackets and servos in place and reassemble and test, so these should definitely fall into the average range others are reporting in the low to mid 20's. We ran into a doubler on the transponder antenna in the way of the one bracket, removed the original roll servo and all the original Autocontrol wing lever autopilot wiring, harnesses, controller, radio coupler so that nothing was left behind and the GPS was rather uncooperative about being removed for the Arinc and RS232 connections as we ran into some stripped heads on rack mounting screws, etc... I think on one with no previous autopilot, no antennas in the way and a more cooperative GPS/NAV/Com this could be done in less than 20 hours with some practice for sure. I also have to say that the kit is very nicely packaged for the install. The blister packaging with all the part numbers makes the install quicker and the pre-wired harnesses are nice as well.