How much do you know already? Do you know anything about HDTV i.e 1080p, 720p, 480p, progressive scan 16X9 vs 4X3 and so on. Ask about colour calibration and if the will do it for you is one thing. Look at TVs that are close by to compare. Pay speacial attention to pure white things on the screen. That's where I find you notice the difference between TVs. Check the inputs and outputs for components that you may want to add. MAKE SURE YOU WILL BE ABLE TO GET IT INTO THE ROOM.

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YAMAHA TRX850