I use both of them. I can't get through the day without xtend, it keeps me drinking more fluids because it tastes so good and it may be a placebo effect that i feel like i recover faster but i don't care cuz i love it. I recently picked up a vasocharge/xtend stack for 17 bucks so i decided to try the vasocharge. I had my doubts on how good it would work, but to my surprise it was the best pre-workout feeling i've ever had. It made my whole body warm and tingly and vascularity improved greatly. It doesn't keep me as energized through the entire workout like a couple other products but it definitely gets me going.