I started w/ Alps/H3 combo, then bought a set of 404s. Eventually, I sold the HEds. I wish now I would have kept them. I really loved those wheels. I think the 404s are probably the multipurpose race wheel, but I did like the versitility of having both.
Were I only going to have one, though...I'd say 404s. Light, stiff, responsive. The Heds were nice, but a bit heavier, and I was always faster on the 404s, except on the flattest of courses.
Look to ebay--you can get some good deals there, esp. if you are still riding 650s.
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