CM370z

Here's my 2 cents from someone that went from springs to coils to air-ride on multiple different cars.

Most higher end coilovers and airride shocks will offer dampening adjustments (the Kw v3s do). This, along with ride height adjustments, will allow you to adjust the stiffness of the ride. However, most coilovers will be naturally stiffer than air shocks but will also have less shock travel than if you were on air. This means that you will have to sacrifice some ride height (you will be higher up) if you go over to air. Obviously, you can control your ride height with air but expect the ride to be softer and closer to the spring feel. The softness would look like this (soft to stiff):

OEM Springs > Aftermarket Springs > Air > Coils

Overall, the comfort level will boil down to your personal preference depending if you like a stiff or soft ride. Personally, I feel like being on air (I have airlift) is more comfortable for daily driving and you do not sacrifice too much stability. If you go to the track, I would stick with coils.

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