I asked my junkyard guy, German Auto Salvage in Boring, Oregon (yes, that IS
the name of the town) if he had any 1.8 turbo motors last time I was there.
He said he had plenty..all blown up.  No good ones.  He was quite critical
of that motor..said he gets em in by the dozens..all with catastrophic
failure.  I am not saying I know for sure that  these are undependable
motors, but when someone is in the salvage business and he tells me to
'forget it'...I'll listen.
  It might be worthwhile to check on what kind of reliability Vanagons
converted to 1.8T motors are seeing.  It's possible my junkyard buddy (I
respect his opinion, he knows his VWs and Audis) may be getting a bunch of
the "hand grenade" turbos from the Import Tuner crowd who're taking them to
amazing power levels..or something.  But still, a lot of money to shell
out for a conversion that may be not so durable.
   One thing about turbo motors is that when kept to a reasonable power
output they can be expected to live, but turn up the boost...and they die,
quickly.  A lot of turbo guys, because it's relativly easy to 'dial in/ more
power with more boost, do it and blow them up.

  Don Hanson