One of the more important questions to ask is how old are you? I know you said you'd like to fit a small family, but is this an indication of planning ahead, or where you are at now? If you have children that are almost in their teens, get a used car and then you'll have a car to give them to tear up when they turn 16. (because teens will do that)
You'll save a boat load on insurance on a used car versus a new car, and repairs on an old car when you wreck may be cheaper (because let's face it, thing like this are bound to happen.)
Not only that, but if you are a new driver, a used car will teach you responsibilty in care-taking with a car, whereas people who get new cars right away seem to think that they don't need any maintenance until 5 years later when they start junking it up. The used and setting money aside plan is good, because people soon forget that just because a car is new, doesn't mean it won't have problems that sneaking warrantys don't seem to cover.
Even more, on a 10k loan, you'll be spending about 4 times more a month that you would with just setting aside $100.
My vote goes to used. It's all a matter of your budget and planning ahead. Remember, the decision you make will last for the next few years in the form of car payments or repair bills. Paying one of those is a certanty, one is not.