IF the new parts are identical dimension wise to the old ones (they SHOULD be, but...) then it will not materially affect the alignment, but for the sake of expensive tires, I would at least check the toe, since even 1/32" in difference in thrust arm length can cahnge the toe by almost 1/4", enough to wear tires rapidly.

BTW, the handling will feel sharper and more precise turn-in wise with urethane, and probably 750 bushings. No adverse change in ride or harshness.

Bob
To install thrust arms, if the car is on a lift, and the shop has the proper puller, the job will take no more than 1 hour for both sides.

I would go with urethane bushings, personally, but lots of folks like the modified 750 bushings, too, though they are not as strong.

Bob

I've got the feeling my upper control arm (thrust arm) bushings are bad, the wheels travel backwards slightly when braking but there is no shake.
What will I notice when I replace them? Will it affect my alignment? Will the steering be tighter?
What should I replace them with? Bavarian Autosport makes control arms with bushings pressed into them, with new ball joints, but are they worth it for 150 bucks per arm? Is it hard to install these alone, and do I need a ball joint puller?
Finally, If I elect to have an independent BMW shop replace things up there, what should I expect to pay for good work?
Thanks to everyone on this board!
James Lee