@Eagle - First bike was a Cytronex GT Transeo; frame was already pretty beefy and with a simple bottle battery and front hub dragged me up hills. It also dragged me and a two-kid trailer up and down through Epping Forest. Battery life wasn't great but as the idea was to help with my (6km each way) commute and to give me enough "assist" that I didn't die every time I got on a bike.. In terms of how it worked? really well, thoroughly enjoyed it, allowed me to go out with my wife and keep up, tow the kids - we spent a lot of time out and about.. It lived up to the hype of "no-hills" as I had to put effort in but I got more out than I put in, if that makes sense..
Fast forward to about 6-7 months ago and it died. The motor was all graunchy, the battery didn't last anywhere near as long as I wanted and TBH the frame was a bit too small in terms of geometry (the things you only find out after a long time...). So I thought about the Cytronex kit and almost pulled the trigger but was taken by the hub/pedal argument and bought blind in an Evans sale my current bike. In turbo mode its pretty damm quick off the mark but suffers every ebike issue of it tapers off at 15mph. Its solid, great for hacking around and secure enough that I leave it at the station (with a couple of locks).
If your goal is to get something to ride like a motorbike then I would seriously look elsewhere! If you want to not be 23 stone then getting a bike that can help you get there is a great plan and really easy to do.. Depending on your level of disposable income you could buy a cheap ebike and know that you will knacker it out over a 6-12 month period (heavy battery drain, constant recharges etc) and then get a better one when you have lost a bit of weight.. but thats if you want to loose weight (my inference, not your post!).
