Our break-in trip for my '08 128i 'vert was in August, 2008. We drove from MD through New Mexico, Las Vegas, crossed Northern CA and took the Coast road through Oregon & southern Washington. The return route involved Montana, Wyoming, Nebraska, etc. back to MD. We covered 8,000 miles - less than 1/4 of which was on interstates - averaged 28 mpg, and the A/C was fine.
BMW air conditioners are rather sensitive to the degree of system charge. They function very well as long as they have the right amount of refrigerant.
I also notice occaisional poor audio (including what sounds like old fashioned tape wow & flutter) on some Sirius channels - but the unit in my wife's Ford sounds similar, so I doubt it's a BMW issue.
Enjoy your new coupe!