Nick,
I bought an '83 633csi earlier this year........just because!
I'm finding the certain parts I need, even used (Ebay), very expensive.
I may have to sell a couple of '02s to keep her going. Looking under the hood is a scary sight compared with the '02 for sure.
Wouldn't want to sway you one way or the other, but, it's a helluva nice ride.