Discount Tire - Extended Coverage? Yea or Nay?

Why not just buy a 5th or even a (gasp) 6th tire and rotate them in? One extra tire is approximately $100 more than the certificates. If no irrepairable flats happen-you win. If you get a flat, you already have a spare you can put into service to replace the damaged one. And no deductible Three years isn't forever. Good chance you damage a tire 5 years from purchase when you have 6/32 less. At that point you would have a wear matched spare to put into full service duty.