For the size (and price), this is an amazing product. It looks great, takes little room in your bag, can be put on and taken off in seconds, and does a good job. Its great for avoiding getting caught out without lights and would be fine for use on roads where there is some additional lighting. However, on my route home, there are some very dark rural roads, and I find I have to cycle quite slowly as I can't quite see far enough ahead to avoid the many potholes on these roads. It doesn't help that I find I have to angle the light quite far down to avoid getting blinded by glare coming up from the front edge of the light: it would be nice if this had been masked by the silicone housing. But on the whole, I have no regrets buying this and would certainly recommend it to friends.
Update: the above was true until I had to recharge the battery. There is supposed to be an LED that comes on to tell you when the item needs recharging and when your are recharging it, when it has been fully charged. This light never came on and despite leaving it for at least four hours, had clearly not done any charging at all as the light then went off on the next use. It now does not work at all. Unfortunately, since I bought this in the summer and have not used it very much, it is now too late to return it.