[DuSh]

Conti DWS is a most common choice for staggered setup that thousands of owners tried and transfer case issue were never a problem. Transfer case in our cars is very robust and problems are very rare. Just so you know same transfer case is used in x5m that has lots more power and torque. Lots of modded x5m with 800+ hp and 700+ torque never heard of any issues with transfer case. People used 20, 21 and 22 inch rims and all sorts of tires on staggered setups

That been said manufacturing defect may happen on any car and any part - if warranty replaces transfer case - that's good, I doubt you will see that issue again. As for star tires - that's a BS if you ask me. All you need to make sure that tire size is correct and that's it. Everything else is a snake oil from dealer. It shouldn't matter what brand you put, star or not. Star tires change from year to year and one tire that was approved by BMW and received a star may no longer have that star next year as they will change OEM supplier. That's like saying you need to buy only BMW approved gloves to properly hold steering wheel. I bought their baseball cap - it looks cool with BMW emblem, but I didn't do it because they forced me to only wear their approved apparel lol. Just my opinion