I put the white spring on my Xplorer, and even tried the green. I actually set out flags and clocked my speed from a standing start as I went by. Both white and green helped on initial take-off, up to 30 or 35 MPH. After that, not much difference. Top speed was the same as stock with either. I went with the green because I felt the white grabbed too abruptly for novice riders, especially in lo range. I have nieces & nephews that need to age just a little before they need to learn how to control wheelies.
Also, I think changing the spring should help belt life, as it will grab harder when it grabs. The trade-off is slightly more abrupt/less controlable slow speed maneuvers.

 

i may need to get a 157. jet.the 160 my be rich for the summertime.