I cannot give first hand experience answer, but i have heard that vari-flow works better. BUT like i said i have only heard, never first hand. I have a buddy that has vari-flow on all his sleds and they work wonders.
"If you were given the opportunity to turn your life around, if someone looked you in the face when you had no hope left and said- 'This is it my friend. Your grace period is almost up. You have three days to do something to turn your life around. Three days to put down that bottle, throw away those pills, make your amends, and move forward with living. What would you do? How would you use your Three Days of Grace?"
http://www.adventurehiker.com/
