winny in an of itself doesnt cause you to lose fat. it is an androgenic muscle hardening drug, which makes an individual already at a lower bf% look more defined. this is why it is designated as a cutting drug, not because it actually causes you to become cut.
its also a TERRIBLE choice for powerlifters. the drug is notorious for making joint and tendon injuries more common.
test prop is fine, but it wont necessarily cause less bloat...if that is what you were shooting for by picking it. it is also a very painful injection.
i would recommend 500mgs week of testosterone enanthate with clen for 3 weeks in the beginning, and 3 weeks to wrap it up. possible winny at the end if you prefer, if you dont mind toning down the training a little.