Saying that it's the best pre-contest drug is an opinion although most would agree it's definately a good pre-contest drug. Masteron itself in a good anabolic with good androgenic effects as well. It does not convert into estrogen whatsoever and is also not progesterone-like like fina is. Winny also does not convert into estrogen nor is it progesterone-like although by itself it's more mildly anabolic and androgenic that winny. Masteron is also the least toxic out of the two being that winny is c-17 alpha alkylated and fina has been shown to be more toxic to the kidneys.