There's been a couple on the LUU's Grunty, eg. this and, perhaps more importantly, this.
I got a set a couple of weeks ago, but will only be trying them out tomorrow night. Testing in pitch dark while walking, they seem fairly bright (but don't set the hills aflame!), & construction seems good quality. You don't get a 'carry-bag' though, just a velcro strap to tie on the battery, which seems a little lacking. Will try & post up my riding impressions after tomorrow…
A lot seems to ride on what you need vs. expectations; being my first set of lights it looks ok so far.