I have a one week old HLS5688W, everything is fine so far, keeping my fingers crossed. I didn't purcahse the extended warranty, however I did purchase the TV on my credit card. It seems that many failures are happening around the 1 year mark... Credit Card companies OFTEN extend warranties of products as long as the product was paid in full on the credit card.
For example, I have a Platinum Visa, and my contract says that Visa *doubles* the Mfr's warranty. If anything happens within that extended warranty, you should contact the Credit Card company to deal with warranty issues.
You guys may want to call or check your CC contracts rather than paying more for extended warranties...
P.S. - This HLS set is a replacement of a perfectly working HLR5067 that I recently sold. The HLR originally had smudges on the screen, and I'm in a no-service zone (but only about 80 miles north of L.A.!) The result was that I got an entirely new set about 3 weeks later. Samsung set up everything through Best Buy (where I originally purchased the HLR), so Best Buy handled the delivery, etc.