I'm looking to buy a new Harman Kardon receiver. I really like HK's so I've been primarly looking at that brand (Dad always used them and love got based done to me). I've been debating between the AVR 435, AVR 635 and DPR 2005. The 435 and 2005 have been going on ebay for refurbs for about 450 to 500 or so while the 635 are about 550 to 600. What would you guys would think would be the smart buy? Thanks.