Saw this on wikipedia:

In an animal model of benign prostatic hypertrophy, andarine was shown to reduce prostate weight with similar efficacy to finasteride, but without producing any reduction in muscle mass or anti-androgenic side effects.[3] This suggests that it is able to competitively block binding of dihydrotestosterone to its receptor targets in the prostate gland, but its partial agonist effects at androgen receptors prevent the side effects associated with the anti-androgenic drugs traditionally used for treatment of BPH.

If this is true, stacking S4 with DHT's should be great?