With the majority of the esters being long, esp with decanoate and undecanoate esters, PIP is not an issue if done correctly. I've made 500mg/ml test with those two several times and they never crash, and that's with barely 2% BA. Twice a week is fine bro, and what Rick means about crashing is that normally it is very difficult to dissolve that much hormone per ml of solution without it crystallizing, or "crashing" out of solution once it's cooled to room temp. You can get around this to some degree by adding extra benzyl alcohol as a solvent, but BA is what causes most of the PIP in high-concentration blends so you don't want to go above around 2% BA, just enough to help dissolve, but mainly to help keep it sterile. If you got your goods from someone, company or otherwise, who knows what they're doing though, I've done it myself many times so it's certainly possible.