I had a ukc8 eled 6watt led which wasn't bad as a primary but it just didn't cut it at 42m in Anglesey vis..
So I upgraded a little (3watts to be precise)to a 3x3watt leds and it is much brighter. My bro has an old UK800R and side by side the theres not much in it, exept my battery last longer
The new UKC8+ looks a good buy, 2 x 5w leds,it has electronic control so you get constant brightness even as the battery drops, downside is theres little warning when the battery does die.
Regards
Karl