i could be wrong, but looking at the road wheels (the track ones don't have an image), i'd say they are just building the wheels using 50mm gigantix rims. nothing wrong with that, thats what i replaced my x-tremes with when they failed (20/20 2 cross, cx-rays). they are okay, i just view them as being cheap and adequate. stiff enough for someone like me who's a mass start rider. if you are a 90+kg sprinter how stiff would they be? i don't know.