It needs premium to take advantage of the extra 10 HP the different PCM programming the MP3 offers. If you use regular gas, it will run just fine, but it will retard the timing and will have the same performance as the regular Protege. But honestly, even the 10 extra HP doesn't do much at all. You might be able to feel it, you might not. But if you're worried about damaging the car using regular fuel, that's not a problem, as the computer will automatically pull the timing to prevent damage. Go with the cheaper gas if you need to, and if you have some extra money and want to get that 10 extra HP, get rid of as much of the regular gas as possible, fill it with premium, drive home, disconnect the battery for a few minutes to reset the PCM, and reconnect the battery. You'll get your extra 10 HP back. Going back to regular, you don't need to go through this, as the PCM will automatically pull the ignition timing as it 'gets used to' the lower-octane regular fuel.
The MP3's advantages are more in the handling department. It has a better suspension and quicker steering than regular Proteges, and this is a difference which you can definitely feel. It is one of the best handling FWD cars ever made, and it manages to achieve this without an overly stiff suspension. Sure, it's stiffer and doesn't soak up bumps as well as the regular Protege, but it is not punishing, even with long trips. Being young, this almost definitely will not be an issue, but be sure to test drive it, including some highway driving on a not-so-perfect road if possible.
The standard stereo is great for a stock system. It has a Kenwood receiver from the factory. Small buttons though.
Be sure to try to hook up with some local Mazda owners if you get the MP3 -- take a look at our
Regional Forums.
I think it's a great first car for a teenager. Not too much power that will get you in trouble quickly, and outstanding handling, and a decent stock stereo. Good reliability, not too old, and not a lot of money.