I am a Trade Plate Driver and use my Brompton to get me to and from train stations and vehicle pick-up locations. Adding a Swytch kit has transformed my working day. I now rarely use taxis and can cover 15-20 miles in a day, cruising at 15 mph with only gentle pedalling in top gear. Although I am aged 70, I can manage most hills without having to get off and walk. Although the Swytch kit does increase the weight of the Brompton, I can still manage to carry the bike up and down stairs at station over-bridges and I regularly take the bike on the London Underground. As others have noted, the quoted battery life is very optimistic. It might be achieved on a very smooth, level surface without a head wind, but in practice, I only get 12 miles out of the larger battery pack. (I always carry a spare battery because of the limited range of the Switch). I use the Bro Block for mounting the battery. This places the battery in an ideal position and allows the bike to be folded without removing the battery. Fitting the Swytch kit needs to be done with care. I had to file the crank a fair bit, in order to fit the PAS disc. I also had to trim 2mm from the front fork ends because the drop-out was too deep to accommodate the locking tab of the anti-rotation washers. The small wheels and high tyre pressure required for a Brompton, can make the ride very bumpy and jarring. I found this could make the main connector to the hub motor separate. I fixed this using three cable ties – one around the cable either side of the connector, The third, tying the first two ties together. I highly recommend the Swytch kit, but don’t skimp on the cost - go for the larger battery.