reality is that biggger and bigger chumks of electronics store's margin are due to warranty sales. As a rule, I usually avoid those, but here are 2 stories where I was glad I DID get a warranty.
46" LED TV (List $2400+ some time ago). 5 year warranty: $299, Getting power board replaced under store warranty 3 weeks after factory warranty ran out: Priceless. List price of repair > $299 and 4 more years left to go.
Bluetooth head set for cell phone (RS) $60, 3 Year warranty: $19. I am on my third bluethooth in the second year. Basically, $69 for one, $89 for three--- over a period of three years. My experience is that the BT headsets last about 12-18months b4 crapping out (Motorolas) with less than a 1 year's manufacturer's warranty.
I never look at warranties for low ticket items. But, sometimes it has paid off for me. Just use my intuition. Luck of the draw I guess.