i'm thinking of running it during pct to help me keep my gains (100mg/day for 4-8 weeks). also, as a bridge to next cycle. i've read the major sides are yellow vision and poor night vision, which is serious but seem to be temporary. also, i've read that supplements for vision such as Lutein and Bilberry extract work to reduce the vision sides. s-4 has passed the first stage of fda testing which is a good sign as well.