tires and oil?
The big question is what kind of rubber do they put on the 18" XWD? Is it at least run flat?
Regarding oil, I would do a stop by a Saab dealer at the half way point since honestly, I feel that this sudden need for or actually the lack of an early oil change comes suspiciously with all of the industry hype about covering the first oil changes free.
Yeah right? 
Suddenly we launched into some modern techno black hole that changes the physics of metal on metal contact? I think not. But what it did do, is free up one bay that would be doing a "freebie" or making money for them (nothing in life is really free), but as a feel good thing for you to sleep better if anything, doing one stop along the route will make you feel better about your new baby.
Me? I go hot and cold (between anal retentive and give a rats), on a lot of these things. True the oil today is better and does not suffer the "shear" of the old oils but when you look at the cost of one oil change and filter versus what you are saving (since you traveled 2,000 miles to get this car), just for piece of mind what the heck.
PS, if you are not on run flat, you should be. The "kit" was just a plug and repair tool to push the plug in wasn't it? And remember that a can of Fix-a-Flat will destroy the pressure sensor with a single squirt. That will be one costly "repair" and the last thing I need in life is to be locating a minor puncture to stuff it on some muddy back road at night. I'll stick to the 17" inch wheels so thank you for setting my thinking right (think Cool Hand Luke heah), really you do not want to run a Haldex with different size rubber. just enough to get home a few miles? That is a maybe that is best left to those who have really done that and sank or swam .... guess work is not a good idea on this one.
Semper ubi sububi in caput tuum