Jarring indeed. I had to get a crack/multiple bends repaired on one of my stock wheels given the sidewall stiffness of the oem rft in general. Cant say I ever cracked or even bent a wheel before, even with multiple cars on low profile tires. Point being, check your wheels for cracks/bends BEFORE getting new tires mounted.
2007 E90 335i - Automagic - Non-sport
Summer: Sonic Tuning ST100 - 18x8.5 ET35 - Conti DWS 245/40/18 - 10mm rear spacers
Winter: Style 159 - 17x8 ET34 - Michelin X-Ice Xi2 225/50/17 - 15mm rear spacers