My leather is nice -- mostly for the smell. My top and side curtains get used once a year, if that, same with the heater. You can only tell I have six pin drives if I remove my wheels. You can only tell I have the ERA rear if you really know what to look for (performance wise, I don't think there's a whole lot of difference between the two). You can't tell I have the QR steering hub, unless I show it off. If I really think about it, I bet a good third of the cost of the car is something you can't see, doesn't
really affect performance, and that you probably wouldn't miss anyway if it wasn't there. After ten years, I'm at the point now where I get really excited about just being able to put a new shift knob on it.