Just put these on my 550, replacing the OEM Contis. Wow! What a difference. I bought them at Discount Tire, exact same price as Tire Rack, plus they give free flat repairs, lifetime balancing, etc. I have the PS A/S on my Maxima and the PSS blows them away.
2008 550i, Carbon Black, Black Dakota, 6MT, Sport Package, Nav, Logic7, Comfort Access, Cold Weather, Folding Rear Seats, iPod