I've just fitted a set of X-Vision LED's to the bike.......
Opinion, they are ok. considering the power used they are a better option than Halogen. However don't expect them to be as good, I bought mine second hand (but practically new), and I would be very dissapointed had I paid full money for them.
I have the wide dispersal lights, they give a dim blue light over the same distance as the main beam. Good for seeing stuff in the pitch dark but not the same brilliance as 'normal' lamps. With one lamp it would be pretty useless. You cannot look at these lamps when they are on, they are that bright, but they just can't get that light onto the road.
Maybe one wide and one 10degree lamp would be a better mix.
The upside is you can easily double these up, if you use a topside bracket and hang another unit under. This would still use naff all power so might be a good technical solution, however this would be more a tad expensive than purchasing a set of Hella Micro-De (about �300) HID lamps, which are probably the best lights I've seen (the normal Fogs are great too), after all it's what TT sell but charge stupid money for the bracket.
www.trailtechproducts.co.uk do a selection of HID lamps starting at around �70. I've not seen them, but I've used their dashboard stuff and it's very well made.