If you're in a 6:1 ratio, Testosterone:Epitestosterone, you should be fine...it's the ratio surpassing 6:1 that gets you into trouble....4:1 in some cases, but this depends on who's doing the testing and 6:1 is normally the standard.
Anyway, even though it's synthetic testosterone, it's just testosterone and your body does not make a distinguishing difference between naturally produced and exogenously provided.
All of that said, keep in mind it wouldn't take a large dose of Testosterone-Propionate to throw your ratio out of line. As for hair follicle testing, I'm not aware of testosterone related hair follicle testing...if someone else is they'll have to chime in on that one.