Yes, the fact the 3.2 2008 has run out of warranty/care would make me worry a little and not knowing the history of the machine. Owner says it works 100%, but one wouldn't know for sure till I buy it.
With a new machine it's untouched, unmolested and has 12 months standard care. Looks like the 2.8GHz quad core is starting around $2499, with a ATI 5770 -- so yes looks like a much better option than the 2009 Quad assuming it benchmarks/test check out 😀
Definitely not the 09 at this time for that price. It's just 49$ off the price you'd have paid 1,5 years ago. Next week you should be able to order a 2.8 quad with better GPU for 2.499. Perhaps even the 3.2 quad with better GPU for roughly the same price (2.899 or so...). Or a refurb 09 for a much better price.