Originally Posted by underscore_
I am looking at the pre 2000 carb models because from what I've read they seem a bit more reliable and of course easier to fix (is this true?).
No, not in my experience. The pre-2000 models are more likely to have waterpump or reg/rec issues. The carbs are horribly complex things with many tiny bits of rubber while the FI is never a big concern. The only advantage is if you can pick one up with the 27 litre tank.
These are trainer bikes made to a budget that are now well past their time. The later F650GS and Dakar are newer, lower mileage and at least made after BMW stopped thinking you'd trade for an R1100 once you lost any license restrictions.
If the only thing that will stop the voices in your head is Rotax powered with a blue and white badge I'd suggest just to buy the newest, lowest mileage one you can. Inspect the oil, learn about the water pump and reg/rec, find the photos of cracked forks so you know what to look for and become very well acquainted with the old info on the chain gang website. You should also look at the tyres, they came with standard spoked rims and tubeless tyres. You can't plug a puncture from the outside, you can't get the tyre off to patch the tube.
Personally, I don't want another walk across Morocco and if I only had the budget for a carbed F650 would buy Japanese.