The W124 is an older design with strut style suspension, but rides and handles exceptionally well for a car designed in the late 1970's.
The W202 has an a-arm style front suspension which is more precise, but only when pushed do the benefits become obvious.
You'll need to drive the W202 to assess it's fit with you. It's a smaller car and interior space is tighter. There are some nice features that come along with the later model:
1. SmartKey has keyless entry, trunk release, and security built into the key.
2. Side bags standard on the W202 beginning 1998, if that matters to you.
3. Five speed autobox (sorted out by 2000) has overdrive fifth for good highway mileage and relaxed cruising.
4. Strong and cold AC.
5. ESP standard - again, if that is important to you. I personally don't care, but lots of people do.
The W202 in 1996- form is a very relaible and well built little sedan. The M111 four banger is turning out to be very reliable, though there are some concerns about supercharger longevity. On that, we'll have to wait and see.
1998 C230 "Black Betty"