Proviron works to an extent to combat the estrogenic effects, but it does not actually reduce the accumulation of estrogen in the body. If you said you were going to do a cycle at 300mg/week, then I'd say you could maybe get by with some proviron. Beyond that I would recommend an AI at a low dose. Aromasin at 25 ed or anastrozole at 1 ed to start and then adjust as needed. Continue AI usage at about half the mentioned doses throughout PCT as well to combat post-cycle gyno when androgens are nil and the body is prone to estrogenic effects.