I struggled with this quite a bit before buying my E500. Personally, I think the early cars look a little more aggressive. Plus, they have extra horsepower/torque. Also, I like the black impact strips. (note: I only considered '92 or '94 models, no '93s)
The newer cars are more subtle but I ended up choosing one because I decided it would be cheaper/easier than upgrading an early car with the other minor upgrades that the later cars received. Specifically, the stereo, power driver-side rearview mirror, bigger brakes, and headlights.
So, in the end, I gave up a few HP for better brakes and lights
