LCD and plasma technologies from the better manufacturers have been fairly reliable according to Consumer Reports, and I would think if anything is going to go wrong with them it will probably surface in the first few months. I know my Panasonic plasma gives 1 year parts and labor, so I'm not sure an extended warranty is really worth it in this instance.
As far as calibration, I think it depends largely on the TV itself and how comprehensive their user operated and service menu controls are along with how the TV is set up at the factory. The best thing to do is read the reviews from the better magazines/webzines and see what they had to do to get the TV optimally set up. For an example, with the newer higher-end Panasonics running their auto-calibration settings seems to get pretty close to optimal and makes professional calibration less or unnecessary. My slightly older Panasonic on the other hand needs to be adjusted through the service menu to get the best results.
I wouldn't buy an open stock item for reasons mentioned previously, and I wouldn't take the advice of any salesman unless it completely agreed with what you read in places like this. They're for the most part worse than useless.
Best of luck.
As far as calibration, I think it depends largely on the TV itself and how comprehensive their user operated and service menu controls are along with how the TV is set up at the factory. The best thing to do is read the reviews from the better magazines/webzines and see what they had to do to get the TV optimally set up. For an example, with the newer higher-end Panasonics running their auto-calibration settings seems to get pretty close to optimal and makes professional calibration less or unnecessary. My slightly older Panasonic on the other hand needs to be adjusted through the service menu to get the best results.
I wouldn't buy an open stock item for reasons mentioned previously, and I wouldn't take the advice of any salesman unless it completely agreed with what you read in places like this. They're for the most part worse than useless.
Best of luck.