yn0t_ : I would assume (and probably WRONGLY) that a "new in-box" purchase on eBay would entitle me to the warranty....

No idea. SkyHigH is the one who said the RioCar manual limits the warranty to only the original recipient. Based on that language, it sounds like an EBay buyer would be S.O.L. But as I said earlier, I've never been asked to provide a receipt when I needed warranty parts or repairs.