I have a 200W kit on my Trek mountain bike. I find that I can get around so easily and quickly that I use the bike where I would have once used the car. I read somewhere that Lance Armstrong averages 400W during a race so I have ‘half a Lance’ boost without the extra weight. I can easily keep up with, or pass, the ‘lycra set’ without breaking into a sweat.
I can thoroughly recommend SOLAR BIKE. I had a battery with a very intermittent and hard-to-trace fault. Matthew was very helpful and reassuring. He offered to replace the whole kit but that turned out to be unnecessary. He was always there with a prompt and helpful email as I worked my way through the problem. He replaced the battery immediately when that turned out to be the issue. The bike works like a dream now.