Hello Feg,
I use my bike every day and I'be been riding my bbs 01 conversion now for 3 weeks and love it, I like to have input so find the system is very good depending on conditions and my energy levels.With very little effort 15mph is a doddle, I plod along at 19 - 24 on the flat and up to 27/28 with the thumb throttle which acts a little like a turbo boost ( you can feel it feed in and I notice the difference). On the hills I find I can climb at about 14 and change down if I need to, again on hills the thumb throttle is noticeable. I get about 35 -40 miles per charge in assist level 7 with use of the thumb throttle using up about 70% of the charge available, to get the best out of the cd you do need to change gear to get the best drive rather then just stay in 1 or 2 gears.