The models are exactly the same except the manufacturer leaves out one or more features on the special model that they sell through the discount houses like Costco on some brands and that keeps the regular dealers happy. For example Costco recently sold two Panasonic plasmas, a 42" EDTV and 50" HDTV that come without the tuner and have a slightly different model number. I'm not exactly sure about that Philips model.
The Vizio line is what I would call a middle of the road plasma, good quality. The Philips might have slighly better picture quality based on their reputation as having plasmas that were at least until 2 years ago made by Hitachi (that might have changed). I would give a slight edge to the Philips.
A much, much better move in my opinion would be to buy a EDTV plasma from a top quality brand such as Panasonic for about the same price (TH-42PD50U). They have been running $1800 on sale at some of the stores like CC. You will get a much better picture on standard and DVD and probably as good on HDTV signals. You will be surprised what a superb picture you will get when you feed a very low compressed HD signal thru a quality EDTV, especially if you sit 8 feet or more from the set.
Best would be to dig deep and come up with about $2200-$2300 for the HDTV model from Panasonic (Th-42PX50U) if you insist on HDTV. Well, well worth the extra $400 or so. Many people pinch when buying the plasma and then spend $500-$1000 on extended warranties and expensive cables (this makes the dealers very happy but is a big mistake). Put the money in the TV and buy decent quality cables such as Acoustic Research or Radio Shack and forget the way overpriced Monster Cables and speaker wire.
Good luck on your choice.
RR6
Costco carries the Phillips 42PF7220A/37 for about $1850 and will be carrying the Vizio P42HD (not certain about the model number) for about the same price. Any one have experience with either of these? Any truth to the rumour that the models carried by Costco don't have the same parts (i.e., inferior quality) as models carried by other retailers?

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