I have the same vibration issues at highway speeds directly after getting my replica 214s on. Despite road force balancing and rebalancing, I am still living with it. Also upgraded tires themselves from Toyo STs to STIIs and still the same. Along with your findings, I'm pretty sure myself it's just an out-of-round rim and I will replace it at some point.

Just FYI, I do have the sport pkg but like others said, that's just an excuse the dealer used. I did not have it bored though... direct bolt ons and it's still vibrating. Yours was definitely a bad rim and even road force balancing cannot fully correct it on a sensitive vehicle like this.

__________________
'08 X5 3.0si - Alpine White / Saddle Brown interior
Specs: Sport Pkg, Premium Pkg, Tech Pkg, Comfort Access, Aero Kit, Style 433 staggered 20s on Conti DWS
Mods: Carbon 35 tint, LED angel eyes, GP Thunder 7500k fogs, H&R 20mm/25mm spacers, clear reflectors, gunsmoke-tinted taillights
Coded: Digital speedo, windows/sunroof/tailgate close via keyfob

X5 pics at Flickr