Well your choice is pretty clear then, however, your install of the MS8 will be a little different from mine because you need to get the wires that go in and out of the MS8 from the front of the car, passenger seat consol area. If you are going to amp everything eventually, you will want to think about placement of the MS8. Mine was easy as the factory amp is exposed and I just attached wires. You might have to run some speaker wire up and down the car (which shouldn't be bad, just hide them under the runners).
What are you looking for your head unit to do?