Whatever extended warranty you consider be sure to read the fine print before purchasing. You need to know whether and to what degree they will "pro-rate" your set in the case of a replacement, whether the warranty carries over to any replacement set, etc.
I ended up with a 3 year Square Trade warranty from Costco; hard to beat $60 for an additional 3 years. However, Square Trade will only cover up to the original purchase cost, so if I have a $350 repair in the 2nd year, I will only have $600 remaining; if the set is uneconomically repairable in the 3rd year, they will give me $600. Still not bad for $60.