drone is a huge issue for me too, i really need to sit in someone's MPE equipped M3 to truly decide. sitting in the middle of a bass speaker at a certain RPM is not my idea of a pleasurable experience. and certainly drone is very very subjective.
2900 is the currentl lowest offer i have seen
2013 E70 X5 50i, Saphirschwarz, Dark Burl Walnut Trim, Multi-contour Seats, Sports Activity Package, Premium Sound, Running Boards