Don't get this shit twisted, masteron isn't much better than primo, and when it comes to prostate it's not the lesser of 2 evils. I believe masteron was marketed and prescribed in Japan to battle breast cancer, so it's anti estrogen effects focus on similar tissue as nolva. It's a DhT, and will also bind to shbg which will free up more test. Primo does this too, just not on the same level as Mast,Winstrol, and proviron. Proviron is also an amazing compound and in your situation may even be the better option. Easier on lipids, on prostate, and still give you some protection for your chesties, I like the lean dry gains from it, I think proviron is very underrated.