I have used POR15 on 10 different cars over the past 15 years and have had great results. Used it on the floor pan of my off road VW Thing inside and out and no peeling for 5 years. Yes wear gloves, hat, glasses... it is very hard to get off skin!
Would not worry about the warranty on the Bilsteins, I not only have them on my 1978 Camaro I also have them on my 1974 VW Thing that I use mostly off road and have not had any problems with the shocks over the past 4 years.