Diesel 10, I have a bonanza with a KFC 150 AP also and have scheduled a dual G5 install but leave in my KFC 150 AP. What is your reason to upgrade to the GFC500 AP? I have considered the upgrade but my 150 works so well for my flying out west that I am having a tough time justifying the increased cost. I also need new interior and a new air conditioner as well... creature comforts that will get my family in the plane more and be happier.... soooo the savings partially covers those costs. Talk me into the GFC500 upgrade over my current KFC 150 AP.