'Axle Promo' means Ford tossed in the 19" wheels for free because you have 3.31 gears. In early September, I bought one without the side scoops and louvers from AutoNation in Houston, TX for $27,800 (after a $500 college/grad student' discount). For a while, I wished I'd gotten one with the 3.73 rear gears since they have better accleration. But, after getting used to the power band of the Coyote engine, I don't regret the choice one bit - True, you lose about 400 rpms at any given cruising speed, but the torque curve is flat enough that it's still a blast to drive. As for the MT82, I too was leery of it at first - I had some inital clunkyness (mine was built in 1/2013), but after 1,300 miles, it's just fine; though I do have a slight squeek in the clutch pedal and rattle in the steering wheel that I'm going to have the dealer look at when I bring it in for the first oil change. Enjoy!
2013 Mustang GT Premium
-MT82, 3.31, 19" rims. Completely stock (for now)