I am in the Air Force And stationed in Germany. I am limited to Quaker State Universal HDX (Dino) and Royal Purple Synthetic. I am almost past the break in period and I would like to go to synthetic. The oil off base is way to expensive Shell Rotalia (Dino) $55 a Gal. Shell sythetic would cost around $75+ a Gal :{ . If you haver tried Royal Purple what is your oppinion.