Dumb Question...
Nothing? usually it will add more features due to having to take two slots rather than one. The advantage of a single din is that not every car has double dins to fit larger headunits.
Other than that, there's no reason to get a larger headunit than you need if it doesn't give you more features.
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LOGIC? You seriously want to invoke logic in a conversation about fake hijackings, missiles hitting the pentagon, and bombs planted throughout the world trade center? I thought it was a given that logic was checked at the door when entering one of these threads.




Now there's some logic!
thanx all