So, what I've found so far going along with upgrading to the sport suspension yourself (really baffling it's not offered here in the US as it's really plug and play). I guess they want people to buy AD. It seems like with AD it's the same for whether or not you buy the sport package (curious how AD feels to the sport suspension on a 4.8/5.0). Anyways... here's the parts to upgrade:
"Front spring strut" 31316781920 $464.16 x 2
Rear (3rd row seat)
"Pneumatic spring, rear" 37126790080 $220.29 x 2
"shock absorber, rear left" 33526781931 $350.00
"shock absorver, rear right" 33526781932 $350.00
"Additional shock absorber, rear" 33536773236 $20.55 x 2
The only catch is the "Additional shock absorber rear" or in layman terms (bump stop) doesn't have a sport + self leveling + 3rd row seat version. Have to pick two. I picked sport + self leveling.
$2,109.96 in parts + labor (probably a day $1k) so looking at $3k. Tough call to do that or just trade it in. I'm leaning towards doing it as I really like the diesel.
Plus, there is still the issue that the non-sport has a larger steering wheel. That's quite expensive and I would think affect the steering ratio feel.
Lastly, I'm wondering if the heavy steering on the 35d can be addressed with software (as it has the same sport steering components as everything else)?
Current: 2012 X5 xDrive50i, 2012 Z4 sDrive35is
Previous: 2011 X5 xDrive35d, 2008 M5, 2006 M Roadster, 2005 645Ci Convertible, 2002 X5 3.0i Sport