The engine sounds so good, so deep and thunderous, it might be the most enjoyable thing about the car. With the Camaro/Firebird gone, they just don't make them like this any more. With a lot of high-performance cars, you have to be going fast to feel the joy, but with the Mustang, even 2000 rpm is fun. Such a broad range of enjoyment adds to the already high value of the car. The GT's V8 feels and sounds very satisfying as you accelerate through first and second gear, upshifting at a modest 4000 rpm. In fifth gear, 2000 rpm is 75 mph, and the engine doesn't loaf at that speed, it rumbles. No engine we can think of sounds and feels like it's doing more at such low rpm. Not working hard, just doing more. This is particularly noticeable in the convertible, with the top down.