Most prohormones have been regularly compared to M1T as the standard, since it had good results and some sides almost steroid like. I did a cycle of it and got enormous back (kidney) pains near the end. Gained 9 lbs. in 3 wks. Lost about 7 post cycle. Thought it was pretty harsh for the losses.
My other cycle was Superdrol, or SD, since it was supposedly close to M1t. About 4 wks, 6 lbs. gained, lost 4 post-cycle I think. Hardly any sides to worry about, except cramps when doing anything highly repetitious, like skating, swimming, and I'd imagine running.
When it was made illegal I gave up any idea of playing with semi-steroids. Especially when the gains were lost so easily and quickly. I haven't seen anyone raving about any of the new PH's out there - seems like everything close to a steroid is off the books.
As far as guys guts go, there are many old 'roiders out there still using and still healthy. Most will tell you that moderation is the key, but I notice that none of these guys are contest huge; just pretty large, usually well cut.