Prices can vary quite a bit by region; check your local Craigslist for comparable bikes.
http://grandrapids.craigslist.org/mcy/5517729256.html is a similar one here in MI for $2500.
http://lansing.craigslist.org/mcy/5526552155.html has less detail, but still seems to be in pretty good shape, for $1700. But
http://centralmich.craigslist.org/mcy/5567760964.html is a NewGen with only 3300 miles and some mods for $2500 too.
http://grandrapids.craigslist.org/mcy/5545725751.html is a 300 with 3300 miles and a little cosmetic damage for only $3000.
Personally, there's no way I'd pay $2500 for that '04 (even though it does look very nice) when I could get the '09 for the same price, or a 300 for a few hundred more. 17" wheels have a much better selection of tires available, and I hate the look of the PreGen. The 300 has EFI and some minor updates that would probably be worth the extra money to me. For me, a $2500 PreGen just seems like a poor value. If it actually has a Fox shock as the sticker implies, that's worth a couple hundred at least though.