It is my only car. I drive it to work (47 miles everyday) and for fun (up to 1200 miles trip). Got great mpg: over 60 mpg when I am not in the hurry and down to 40 mpg when I am. So far drove about 16k miles in it without a single glitch. Accident avoidance ability of this car is nothing short of amazing.
I bought my smart fortwo Passion Cabriolet as my daily driver. Remember that it is a two seater with a small trunk.