I bought my car from Carmax 3 1/2 years ago with their 4 years extended warranty. I must say that for me their extended warranty worked very well. I have bought 4 cars from them in the last 5 years which 2 BMWs and do not have to complain. They do not have the best mechanics but I never had to argue on anything related to the warranty.

Good to hear that they have taken good care of you. I've heard very good things about Carmax and their extended warranty seems to be very reasonable (in terms of price). I would certainly consider that route on my next car...sure beats taking the depreciation hit on a brand new car.

cv boots dropping like flies - maybe the aftermarket ones on ebay are better?

SELL YOUR CAR!!!!
Without the warranty you will run into MAJOR costs. Did you know a new/rebuilt transmission from the stealer is $6000 to replace? Odds are pretty good it will go out and you don't want to be stuck with that.

Just my two cents worth.