Personally, if the images look equally good, I've always followed the rule of "Buy the largest you can afford, or that will work in your seating area." Think of it this way: You buy the 30" and it looks great... but you will always ask yourself "I wonder how the 34" would have looked?" I would bet if you get the larger set, you will only say "Ha! The 34" kicks butt!" Then, many months down the line, you will ask yourself "I wonder how a 50" would look?" I don't think anyone ever asks "I wonder how a 27" will look?" anymore.
Up close in a store it is difficult to tell the difference in the screen. There is a couple inches difference but that is it. For the difference in price is it worth getting the 34 in or not. All salesmen swear the technology is better in the 34 in and that is the only way to go. Are they correct or just being salemen?

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