Vforce is more mid range to top end. Rad valve is more bottom end to mid range. That being said, its all splitting hairs at the reeds point. There is not alot of power to be gained by reeds compared to other mods such as porting. I currently run V-force 3 reeds in my MX bike, and Rad valve in my XC bike. But i wouldnt even hesitate to swap the two for a race, i doubt i would notice much of a difference.