Well, if you want a more "future-proof" receiver, go for the 55TXi. It is currently one of the VERY few $1000-ish receiver that supports the i.Link/FireWire digital connection for the SACD/DVD-A players. I would comfortably predict that most, if not all, AV receivers AND universal disc players will feature the i.Link within one or two generations.
The only significant difference between the 53TX and 55TXi is the i.Link (others are so minor, such as the USB audio and a slightly better remote). But it may well worth an additional $200, if you plan to keep it for a long time.
