Hi, I have an SBP shift kit & thoroughly recommend it. I got the deluxe that cost slightly more but u get everything needed including some tools & an upgraded chainring freewheel. I've had it for at least 18 montths, probably more & in that time it has given zero trouble. The only maitainance I've done was a slight secondry chain (jacksaft to chainring) retension in the 1st week after fitting it. If u want the ability to climb hill with ease & still have all ur top speed, I think these r the answer. U also get the bonusrs of 1; ur motor is triangular mounted to ur frame. 2; no more dodgy chain tensioner/idler. The 1st of these reduces vibration a bit, the 2nd reduces vibration A LOT. Another bonus ia no more rag joint mounted sprocket. Mount it properly the 1st time & u'll have no problems. Cheers