Thanks for posting XMcBainx. I have the same question, and wondering 2 other details specific to my own sitch.
1) does the answer for tires change based on the amount of driving done? i.e. my TI is a second car so i don't drive it as often...
2) wheel annoyance - - i have the originals wheels from when i bought her. they "seem" fine but the BMW decals that were in the center over time i guess fell off
I really don't want to get new wheels just for the BMW logo but it looks dumb since they fell off! Options ?