My warranty paid for itself 5 times over as well, before I even hit 80k miles - but then again, on a B7. So for the 760's and B7's, the warranty is an ABSOLUTE no-brainer - but on the 750's, I'd say it is worth the piece of mind at maybe 4-5k max.
Maserati GT 4.2
Range Rover 4.4
Dodge Ram 1500
PAST: ALPINA B7, e63, e39, e39, e36