LG vs Hitachi TV

LG is from Korea and Hitachi is from Japan.

Consumer Reports seems to rate Hitachi fairly high for picture Q and reliability. Check the ratings/reviews on Amazon.com, as you may find if other people have had good/bad experience with either one.

I would guess the dealer wants to replace the set to you (instead of the more common warranty repair) as a "good-will" gesture and changing brands may be what they consider the better deal. Without the track-records (incidence of repair, MTBF, etc.) of the specific models, this becomes a Honda vs. Toyota vs. Nissan debate. The difference is that most modern consumer electronics manufacturers don't really give the consumer many qualitative reasons to chose one over the other. I should add that one division of my employer is a warranty servicer of many brands of consumer electronics, and they have plenty of work! (LG and Hitachi included) They tell me that, in general, the new TV sets will not last as long as those made 20 years ago. (that's not to say that a failure in less than a year is "normal" or "acceptible") The new technology seems to stress the components and everything is made to sell for as low a price as possible.

All of that said, I think you should accept the new set that is offered!