My car has a very slight, but noticeable wobble at around 70 mph. It's odd, 60 is fine, 90 is fine, it's always around 70mph. I've had the tires balanced, and they only have about 5k miles on them so wear isn't the issue. Keeping on top of tire pressure helps a bit, but even when the tires are right on spec it still shows up (albeit very, very slightly at that point). It really is quite mild, you can feel it a bit in the wheel but it's not like a shake/shudder, so I live with it. Next time I take it in for service i'll inquire more about it.
E88 N54 Alpinweiss/Coral Red/Motiv HTA 3586r Tial .82AR/Meisterschaft Race/Berk Resonated/ER CP/Synapse/VRSF FMIC/FFTEC LPFP/HFS-4 DO Stainless Lines/BMS Thermostat Delete/Rob Beck PCV Valve + Cap/BMS OCC/ST Coilovers/M3 FCA + Tension Rods/M3 Subframe Bushings/M3 FSB/AA Strutbrace/DINAN Camber Plates/Apex ARC-8/Project Kics/VAC Hubs/Rogue Transmission Mounts/Alpina TCU Flash/Icarbon/Kerscher/BMW Performance