I generally don't get into questions like this, but having owned an driven each of these cars here are my pros and cons. By the way it really is like comaping apples to oranges as they serve different functions well. Mustang: pros - overall great car to start to customizing, plenty are availible in very good used condition (check Carfax, test drive before you buy, ask to see maintenance records), lots of factory and aftermarket options. Great looks. Can turn into a sports car or a drag car. Cons: if it is your primary car, and you have young kids it is a struggle with child seats (been there, done that). Limited luggage capacity for trips. Not sure-footed on icy roads. The 300C pros: overall great car to start to customizing, plenty are availible in very good used condition (check Carfax, test drive before you buy, ask to see maintenance records), lots of factory and aftermarket options. Great looks. Decent mileage for a big car (I got 24 mpg on a highway trip with the multi-displacement hemi engine). Comfortable interior. Better on long trips, can tow a trailer with it. Availible in all wheel drive. Cons: because it is a big car, it takes more engine work to turn it into a really fast street racer. Not as many ways to race a 300C (Its not a car you're going to take sports car racing). So what's your priorities? Then choose. Good Luck