Proviron is great when using a lot of test. It binds strongly to the SHGB receptor, thus making the test you use be free to work its growing magic. It does help with hardness due to the lack of conversion to estro, but that will only really show if you're low bf% already. It's also great because you don't have a huge amount of estro that you need to control when you come off, so PCT is a breeze. I use proviron all the time, i love the stuff. I use 50mg a day when using a heavy test cycle, and i works great. It does give some people constant erections at 50mg or over, so be prepared. (Not a bad thing most times IMO)
Hope that helped bro.