I'm 81, have raced and toured for most of my life. I still cycle almost every day, usually around a 5 mile slightly hilly circuit through lovely country lanes. I have arthritic knees and very painful back-pain, which feels at it's most comfortable when I ride. So having got my position just right on my old racing bike, I did not want to risk buying a new e-bike which did not suit me, and anyway, what's the point of buying another bike when you already have one you like?. I therefore, I ordered the Pro kit in January and it arrived in May. Fitting it took less than an hour after, widening the dropouts slightly (using a grinding wheel was very quick, but you have to be very careful not to overdo it). The performance has exceeded my expectations. I have it permanently set on 60 % assistance (the minimum) and no speed limit, which is really for off-road use, but you don't get that sudden drag feeling when you crest a hill. I think the 15 mph speed limit legislation was probably devised by a committee of non-cyclists, because I am not travelling any faster than when I was young and fit. Initially, the battery feels heavy on the bars and some of my friends have made brackets to lower it, but I soon got used to it and do not find it a problem. My only (slight) complaint is the price of the extras. The Pro kit is £124 more than the Eco kit and the black wheel is £50 more than the silver one. Having bought black rims in the past, I know that they are only slightly more expensive than silver. Since reaching 80, I was getting more and more aches and pains and loosing muscle strength, and cycling was becoming an unpleasant chore; but this has renewed my enjoyment and enthusiasm, knowing that the ride will be as hard or easy as I want to make it according to how I feel on the day. I can get 30 miles normal use, and much further if I am cycling with friends who are slower, so I can save the battery by switching the motor off on the flat and down hills. There aren't many panaceas in life, i.e. you think you have found the answer and then you find a problem – but the Swytch kit is everything and more than I wished for. .