The kit is very good and enables me to continue using the bike that has been my favourite for many years. Easy to fit and just the right amount of help for my aging legs. All instructions on PDF are thorough and easy to understand. Messages sent via this website do receive helpful attention quite quickly. There are just a few niggle which means that I only give 4 stars. I had to pay upfront in full and wait over 4 months for delivery. UPS delivery is appalling. £700 worth of kit was left on my doorstep while I was away from home. It could easily have been stolen and the loss would be mine. Similarly when I purchased an extra battery, UPS dumped the package on my doorstep without contacting me. There is a problem with the OLED control panel. The power level buttons are too small and difficult to operate while riding. A small bump in the road can send the power level way up or down to zero. I hope that this might be improved.