OK back to the airplane, I bit the bullet today and came home with a 1/2 gallon kit of Klass Kote primer. Sticker shock for sure but out of all the alternatives out there I have tried nothing works as well. It fills very well but sands easily. The really nice thing is that I can get it in primer to see any flaws, take care of the high and low spots, another maybe two applications to get it perfect and apply wax and PVA right onto the primer. I really don't see the need to have to spray an actual color onto it. Of course the last round of sanding will be wet 1000.