Besides the other benefits of the Whites listed above, they roll very well.
And the Ti freehub can handle large solo cogs without notching.
The decision comes down to do you value durability and low rolling resistance more, or light weight and lower price more?
Oh, I've had WI before and really have liked them. I'm leaning toward getting a set, then if I don't like the wheels with whatever carbon tubular rims I end up getting (that's a whole 'nuther thread so won't go there) I'll still have a set of awesome hubs.
If only I could find a set of 24/28 H2/H3 for Campy; I do like those aesthetics better than the T11s...