If you get a traler with a swivelling bow (Trailex for sure, not sue about KH), it is specially designed to allow you to transfer the boat from trailer to dolly and back on your own.
... The only way I think the trailex trailer bests the kitty hawk (having compared both in the parking lot of a few events) is the spring setup on the trailex. The trailex's springs are lighter and probably better thought out, but the kitty hawk ones are more than adequate.
Gotcha. I was looking at it as a positive from the perspective of a single laser--I figure the lighter springs will be a bit kinder to the boat.
Also, vassilis--I got mine directly from Nautical America, the maker. You can find contact info somewhere on this site... Not sure where...