I don't think you can go wrong in the say 88 to 92 timeframe. The 90 to 92s are a little more refined, automatic down windows, windows controlled by the key, wood on the door, leather standard on the 3 liter, etc. I think it's basically a luxury versus utility question - if you're really looking for utility go with an 88 or 89. They are lighter, no airpump, MB tex on most 3 liters, etc. I would say stay away from pre-1990 leather.