Same year as the other two!
Aside from that, 928S have a sort of slippery slope when it comes to performance. If you decide to get a 32-valve, you're looking at 85 and up and an extra 50 or so horses. Get an 86.5, and you get the 87 suspension, which is better. Chip either and you're adding another 20 horses. Then for a bit more money, you get the '87, which looks nicer and has more features. Then you're looking at the 89 and up GT and thinking about selling the house...
The 911s move up incrementally, the 928 improved by leaps and bounds.
The '83 is fine for me: easier to work on than the 32-valve 5.0L, plenty of torque, and not as huge a nightmare if the timing belt goes. A few simple mods to free up the breathing can make it more sprightly if I want, but I don't need the full 171-mph rocket-sled of a car experience.
What's weird is how hard it is to find a decent one for sane money (less than 10 grand) in the colors I want. I'd never have believed it could be tough to find a red 80s-vintage Porsche.
Emanuel