I�ll try and take a stab at this:

80 (?) to 83.5 :

aircooled if that�s what a person likes.

Maybe easier and cheaper to rebuild.

No coolant changes

No water pump failures

Did they come with AC?

83.5 to 85 :

watercooled 1.9 engine.

My heat is great, I�m in mid-west snow country.

The rear heater fails every 5 to 8 years (?), but it�s easy to replace. It�s
nice.

The very early waterboxers and diesels have steel coolant pipes under the
van that rust out sometimes. My 85 has the plastic pipes.

1.9 engine has a reputation for a stronger bottom end than the later 2.1.

1.9 has the digi-jet ecu which is not as advanced than the 2.1�s digifant.
But the digi-jet ecu itself  has a reputation for rarely failing .

The 85 GL models and some 84 Wolfsburg editions have plush captains chairs
and  a very nice tachometer.

Dealer installed AC, which is prehistoric compared to US autos. I�m working
on getting mine running, but one person wrote that it�s operation is just as
noisy as having the windows down.

Better headlights than the square light later models. I put H4s on mine with
a fused relay setup from the battery. Nice.

86 to 91:

The 2.1 engine has a power chip available, plus a hot cam etc.

Some models have power windows, mirrors and locks. Nice features but not
trouble free. Check them out for quirks.

A factory AC system, I don�t know how well it works.

The later Caret model has body moulding which looks nice.

All Models:

The body seams rust behind the seam sealer caulking. Look close at the
seams, you may see some trace of rust.   $$ to fix if it�s advanced.

Changing the 10+ year old  coolant hoses may cost up to $400 before labor.

Need to change the fuel hoses at $60.

Water pumps fail every 60K (?). The first time may be an 8 hour job to R &
R.

Check to be sure the front heater blower works well , you  need to pull the
dash to replace it.

Some gas tanks leak from the gaskets on top of the tank when they age. Not
the most fun job to R & R.

For some reason the gas filler nozzle will spit gas back at you when you're
topping off the tank.

There will be some Fuel Injection quirks to trouble shoot, but some people
are interested in learning about the FI system. I enjoyed it.

Neither the 1.9 or the 2.1 has much power going up the mountains I�ve heard.

Alloy Wheels are very nice.  $$$ on e-bay. Lug bolts themselves are $10 each
for some reason.

Some people like the waterboxer and some don�t. The person who came up with
the digi-tool diagnostic tool who has had the subaru conversion  as well as
some waterboxers said � IMHO it�s easier and cheaper to just fix the
waterboxer.�

My $.02,
Mark Ingalls
85 GL
75 Standard Beetle

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp