Are you asking whether you should replace the turbo with new?To replace with new or clean and replace actuator?
First see if the lever on the turbo itself can move or whether it's stuck in place due to carbon... If you can persuade it to move - gradually increasing the range of motion to about 3/4" inch, then just buy a new actuator and follow the guide here on adjusting it. (You'll need a Mity-Vac or Princess Auto copy.)
A new actuator can be had in Canada for $115 plus shipping (unless you also buy a filter kit - in which case the shipping's free) at http://www3.ns.sympatico.ca/roseland/VWPartsA4.htm or for U$99 shipped from http://www.metalmanparts.com/product.sc?productId=352&categoryId=-1 (there are other good vendors out there...)
All the best,