Subaru's DO have weird problems, despite what all the pundits say.
 They always say "Well, you only hear the bad stuff when you read the Yahoo
Conversion list"  but here's one mentioned right here on the Ole Vanagon
list.
 Imagine, if you would, you are a dummy with money who's had the conversion
done by a pro.  You are on a long trip, far from your shop and this speed
sensor fails.  Where do you take the van?  Who will you get to work on it
with any degree of success?  You go to the local VW guy, he laughs.  You go
to a Subaru guy, he laughs.
  Not saying I wouldn't convert my van that way if I wanted more power and
needed a new motor, but every solution has it's compromises, and installing
a Subie motor seems to often come with "head scratcher" EMS-sensor- wiring
harness related glitches.
  Don Hanson

I recently did a Subaru conversion, and in the course of the conversion
removed
and cleaned out the gas tank (which was quite clean) and replaced all the
fuel
lines.  Soon after I was on a trip and had some behavior that seemed like
the
fuel pump was on its way out (it was 8 years old by then) so I ordered a new
one
and had it sent by greyhound close to where I was camping.

I replaced the fuel pump, and then found out on the trip home it wasn't the
problem (it was related to the speed sensor).  I also found that almost
instantly the new fuel pump started making the noise again.  So, now I have
a
brand new fuel pump and an old 8 year old spare.