I've only driven 15 miles on my "new" 07' E63, but these past couple months where I've acquired parts, STAR, Rotors, Control Arms, refurbished OEM front Airmatic Struts, SLS Buckets, Headbolts etc. I've discovered while attempting to remove my heads (not happened yet! But very close!!) that the Power Steering Pulley itself was messed up enough to potentially cause catastrophic failure should I cast a blind eye. I mean how rediculous would it be to spend all this time rebuilding the suspension, taking off the heads to get rebuilt, having the Intake remaned, as well as ultimately having the heads rebuilt with the latest high tech Rottler P69AHD and Newen Contour-BB and put everything back together again to only have a "break-down" due to the Serpentine Belt exploding because a shoddy P/S Pulley??? It looks like I'm going to have to remove the P/S Pump anyway in order to disconnect the Air Hat Emission Hose on the driver side from the front bottom side of the Head. Being that the stealership would charge $1400 for the install and a new one is $380, it's a no-brainer as it's just adding on to a total net savings by doing this stuff DIY!!!