I've had the 1519 "Vanos mechanically jamming" code on my car for about 2 years now. It took a long time for to figure out what was wrong, but ultimately Rocco fixed it, and the car runs considerably better. The vanos not working is a relatively subtle change from how the car normally runs, but it is very noticable. At low RPM's (particularly idle) there was noticably less power, and the vanos unit made a lot of noise.
The solution was purchasing the besian seals replacement kit:
http://www.beisansystems.com/products.html
(around 30$)
The installation is somewhat involved, and can take a few hours. Rocco did mine for 225$, as everything came apart quite easily. The price on a dual vanos system would likely be more. I took the opportunity to change the valve cover gasket while it was being repaired, as this did not involve any additional labour.
The car now has noticably more power, and im guessing i'll be getting at least 100 more KM a tank.
Thanks!