HK's warranty is the best I've seen for refurbished receivers.
I would buy one if I found a good price.
But on Ebay, people are nuts! I have been looking for a deal on a refurbished thru Harman Audio, but some idiots keep bidding up the price until they end up buying the refurbished unit for about $20 less than I can get it for new.
So I am likely just buying new. To me, I would need to save about 40% off new to make it worthwhile. (thats 40% off whatever price I could get it for, not the MSRP)