I think they're ugly. And slow. And a bit more complicated than a simple 500 twin needs to be....
But hey, that's me
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Worth is relative. Depends on where you are, the demand for that particular model, how much the seller likes the bike, and how much the buyer likes the bike.
I wouldn't pay more than 800 bucks for one, in good condition. Hell, I wouldn't pay anything, to be honest, but if I had to buy one... yeah.