I ordered 2 of the 50 mile kits in March 2018. The reason that I bought two was that I realised that the 250 WHr batteries claimed to give 50 miles would likely give me about half of this range in the hills of North Yorkshire. I realised after a few weeks that they might be delayed so I bought a Kalkhoff 600 WHr e-bike with hub gears and a belt drive costing £2600. This bike was good but had clicks almost right from the start. In the end I had to have the motor replaced. The Eco mode of the bike showed 118 miles but in the hills of North Yorkshire it was getting just less than half of this. In February 2019 my two kits arrived at last. I fitted them to my two bikes. There was one fault with a battery unit which was fixed fast by the Swytch team. I fitted one kit on my Koga bike with 14 hub gears (same bike as Mark Beaumont cycled round the world on), and one kit on an old Genesys bike. When I go out I take the spare battery in a pannier and switch when the other battery is getting low - about 25 to 30 miles on the hills. This shows that the Kalkhoff bike and the Switch bikes get about the same fall-off in range. The Kalkhoff bike gives a smoother increase in speed but I actually enjoy the Switch bikes a bit more as I feel more of a kick and the bikes are lighter. I have increased the maximum speed from 15.5mph to 17.5mph (illegal) and it is now even more fun. I like to cycle at the maximum mode (5 out of 5) which makes it really responsive. I have cycled in total about 1100 miles using the Swytch kits. Some of the rides around here have very steep hills and I then take the Kalkhoff bike as it has more torque, but the Swytch would also get up the hills but not just as fast. I am very pleased with the Swytch kits so the wait was worthwhile.