I bought a 2000 XO-1 with moderate cosmetic wear, non stock (cheap) wheels, and otherwise mostly original components for $300 last year. I think that was a good deal, but I'm not sure I'd pay a lot more than that for what you're looking for, as the Sora drivetrain isn't that exciting. The bike you're looking at is after they adopted treadless headsets but before they adopted carbon forks on XO-1s.
Everything else aside, I think they're pretty nice bikes.
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