I would recommend checking in with your retailer, and looking at the set that they have on display. If you're seeing the same issue on the set that you decided on, you might discuss your options while you're within your return policy. At the end of the day, I want you to be happy with your Samsung product, so I would encourage you to do what makes you happiest.
I purchased the Samsung LN46B750 LCD because of the strong comments I saw on the web for this set. I was interest in LED but heard that blacks shifted very quickly when not viewed straight on. So, I've been surprised with the poor off-axis viewing I'm getting from this TV. If I move a body width left or right, black on the screen (e.g., Ricky Gervais' suit on the Golden Globes) gets lighter. Another foot or so and the whole screen is much lighter. I know at sharp angles, this is a problem for LCDs, but I didn't think it would be an issue for one cushion over. In fact when I stand up (the screen is eye-level when seated), it gets lighter. I did not notice this in the store, though their lights are much brighter. So, is what I am experiencing just a problem across LCDs, is it a particular problem with the 750 (my friend with a 650 says he doesn't notice the problem) or do I have a bad set. I need to decide in the next week whether to return or exchange. If you have a LN750, please let me know your experience. My settings are Standard, Backlight - 5, Contrast - 85, Brightness - 45. I sit about 10 feet away in a fairly dim room. Thanks.