If I were you, I'd hold onto the '08 simply because selling a salvage'd bike can be a pain. The '04 will have more obvious value, I think. If you have the stock parts, you could sell the aftermarket stuff and sell the bike close to stock and do better, I bet.
Unfortunately I don't track liter bike prices so I can't offer any suggestions on reasonable starting prices. Does gixxer.com have a few of each listed? Might be a good starting point and you could even PM folks who listed theirs as sold to see how much they went for.
Dragging knee is for the track, and dragging tail is for the lot. --Kane Friesen
When you're in a car, you're watching a movie; when you're on a bike, you're in the movie. --Robert Pirsig
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