Which specific Dr. Vanos upgrade(s) are you referring to? I've done the Beisan upgrade (Vanos exhaust oil pump disc with smaller hole for hub), rattle kit, and seal kits. I don't hear the metallic marble noises around 2800 rpm anymore. Not sure what caused that noise (the slack between vanos disc and hub or the excess play on the splined shaft), but it's super quiet now after the upgrade. I did it mainly for the peace of mind of minimizing the hub tab failure than anything else - all the others were "while we're in there" sort of things to do.
I had skipped the solenoid upgrade because that can be easily replaced if and when it failed.
While doing the job, I found that the upper chain guide was already in bad shape at only around 44K miles, so looks like only a 50K-mile replacement item
For more pictures of my upgrade, see this =>
http://www.zpost.com/forums/showpost...&postcount=730