I have considered and studied this issue of suspension choice for some time now and have decided to go with the air suspension over coils. My previous experiences with air suspension systems and the obvious lack of any time tested evidence of sustainability of this model S system being available due to the relative newness of the car left me concerned about the long term viability of this option, but I worry no longer. I base my decision on the following: -This is a sealed nitrogen system; it is unlike other OEM manufacturer external air pump systems and at least "seems" much less susceptible to the external environmental factors that can lead to failure down stream. -I see Model S as basically a rolling computer. Personally, I don't believe coils offering the shock and component protection long term that the air suspension offers. I always opt for padded protection for my laptop, so I opt for the same here. -Ride height options. This is obvious over springs, and even though the coils seem to ride at very close to the "normal" height setting with air suspension and the ride will very likely stay at "normal" most of the time, having the option to raise height in the field to address obstacles given the potential damage and the money involved in this purchase, I opt for air. At the end of the day, I see it as close to a 70/30 decision, and I'm erring on the side of caution. Happy to entertain counter-opinion and evidence to the contrary.