I actually just had mine replaced today! Mine was making a clicking/grinding noise, and with my warranty expiring in 2 days, I decided to bring it up. Fortunately it was covered because it's a $200-$300 part! Also getting my headrest replaced, since the headrest "flaps" no longer stay in position.
2008 BMW 550i M-sport, 6sp SAT, Jet Black/Black Dakota leather, prem, nav
Mods: matte black grilles, 18% tint, GP Thunder 8000k AE, Nanoshield paint protection film, 15mm TMS spacers