Going to get a GMPP before my 3 years are up on my b2b factory warranty. I found a dealership in the mid west that sells them at a substantial discount. Since I'm putting a lot of mileage on my Z, the 5/100K/$100 ded looks pretty good for about $1600. I'm hoping the price hasn't gone up much as I got the quote about a year or so ago. This makes the most sense to me as Edmunds said the 2012 predicted repair costs over a 5 year period was about $1500, last I checked.