Some interesting comparisons of 7" LED units here...
http://betterautomotivelighting.com/...light-is-best/
Some of the info is relevant but not sure how many of the units would be available in the UK and if they are right hand drive.
It's good to see all the lumens and lux figures in one place.
Wish I could find something like this for bulbs and bulb type reflector/lens units.