Break rotor replacement and alignment at the dealer?
The other thing that always annoys me is the relative lack of knowledge out there regarding Mercedes-specific mechanical work, including simple tire-mounting. They should use zinc sticky-weights, not lead ones, and no the lug nuts don't have to be re-torqued after a certain distance, and you should have them torqued to the proper N/m figure (I think it's 90 or less) and should you ever remove your wheels and put back on later (as in summer/winter sets) you need to pay attention to directionality (ie. the tires shouldn't be put on a different side of the vehicle than they came off-of). Jacking up your vehicle is also an area to be done carefully at the indentations for jacking. Mercedes knows all of this already.
In general, tire shops have better (newer) equipment for both mounting and balancing and aligning tires than the dealer. I have used costco and discount tire with no issues at all.
The one benefit with the dealer is they have the specs for the alignment, so as long as you confirm any shop knows the factory alignment for your car you should be fine.
If alignment is really needed, I will stick with the dealer.






