They are definitely lighter than my stock Bontragers. I'm still waiting to hear back from them on my weight question, but if I had to guess, it's probably about a pound less for the set. They definitely feel lighter on climbs and in general riding, but part of that might have to do with the GP 4000s II's, which seem to have much better rolling resistance than my Bontrager R1's.

Here's a slightly grainy close-up pic of the rear wheel. You can really only see the VUELTA CORSA when you're up close.