I assume you have a typo there and you meant the Acura MDX.
Well my friend, it is like comparing apples to oranges, both VERY different cars. Lets begin seeing some differences.
Acura MDX is a large SUV starting at ~$41,000 while the Chevy Cobalt is much less. Seeing that GM is officially going bankrupt you can probably get an amazing deal on the Cobalt as well. If you are thinking about saving money go with the Cobalt. I can type all day but I'll just make a quick list of what I know.
Acura MDX
Large SUV
Expensive
Luxurious
VERY reliable (Acura is A.K.A. Honda)
Fuel inefficient
Chevy Cobalt
Sedan/Coupe
Very cheap (price)
So-so reliability
Basic necessities, not luxurious
SS Cobalt is really quick
Fuel efficient
I'd pick the Cobalt. I prefer Japanese cars but you are saving so much money with the car itself and gas. The car is quick. It might not be as luxurious but you can get it COMPLETELY fully loaded and still have lots saved up vs a basic MDX. Rest you can spend on tuning or whatnot.
