all absolutely true attributes with s4 and then some... the strength is awesome as well as the vascularity and muscle hardening... endurance improves and recovery as well...Hell yes. I see and feel the difference in my performance. Little to no rest in between sets. No soreness after my training. I hope that other people are going to try out S4 because the potential with it is limitless. I will not do another cycle without it. When I am ready of course.