I have but I have not finished the car yet.
Por15 has a metal prop which is generally used for it. The metal has to be properly prepared for it to stick well. My car was originally soda blasted and that's not enough. I chose not to use the associated "Metal Prep" because I did not want to deal with water, acid, liquid in areas I could not control.
Basting was a great "dry" prep for very good adhesion.
I blasted every corner one by one. I would spend all afternoon and get maybe an area equal to 6'x6' blasted. At the end of the day when each segment was blasted I BRUSHED on POR 15 in that area. I did not spray it on. I could have but great caution has to be taken as it is very bad if breathed.
I covered each non-body area. Rest of the car was done same way except etch primer was sprayed on.
I am contemplating what to top coat it with. In areas I have gotten etch primmer on it, the etch primer has stuck very well and been a very good base. I like the POR15 for under body as it is not as thick as some undercoatings but it doesn't chip. If you take it of with a sander or grinder it kind of moves around like an oil patch. Odd stuff.
http://www.rc-tech.net/pantera1/strip/strip.htm