I bought one of these last week for £7.94 + £2.94 delivery. The price on ebay is currently wrong and I have informed the seller.
eBay - The UK's Online Marketplace
It came in about 2 days and I ran it on AAA batteries. At maximum brightness it is very bright for about 1 hour and then slowly fades away. I have just taken delivery of a 18650 battery and charger from the same vendor and a rundown test with this lasted about 2 hours at maximum brightness. By this time the 18650 was done to about 3V. Another 0.5 hours and it was down to 2.8V, dimmer but still usable.
The torch mount is just rubber and you jam it into place. Looks a bit primitive, but seems to work.
On full brightness, this really lights up the path in front, even on wide beam mode. Even on dim mode it is brighter than my existing 1W LED light. I would not use this on flash - it is just too dazzling to pedestrians and motorists. I will continue to use my existing LED on flash, with this as a backup and bright headlight for the darker parts of my commute.