W202 vs W124
My wife's parents recently sold their '60 190SL (W121) and '83 230E (W123) and purchased a low kilometre '99 C200 (W202). They wanted to stay with a four and had hoped for a C220 or C230 but both are fairly rare here in Australia, the C180 and C200 being the most common with the M111. Here the C220 was dicontinued in '96 and replaced with the C230 which in turn was discontinued in '97 and replaced with the C240 (M112 V6). Since they had a preference for something recent with a four, they ended up with the '99 C200.
Just last week they made the 950km (each way) interstate journey to visit us (and show us their "new" car). I inquired as to how they found it on the trip to which the response was they wish they had gone for a W210 (E230). Whilst the handling was an improvement over the old 230E, they were disappointed with the ride and comfort of the C200. To make matters worse, during their stay they rode in our '90 300TE (7 seater needed for 4 adults and our 2 kids) and claimed that the 300TE was much better riding, smoother and quieter than their C200. They had forgotten just how impressed they have always been with our W124 wagon.
I had an opportunity to drive their C200 and found it a bit under-powered compared to our cars. I also found it to be noisy when accelerating, even compared to my 190E-2.3 (M102 four cylinder), and the C200 is also not as quiet as my parents '96 E230 (M111 powered W210). The C200 does idle more smoothly than the M102 in my 190E though. Possibly the C230 with more power and torque would be better. I would probably descibe the difference as being that the M102 and M103 sound relaxed whereas the M111 sounds busy, (as does the M104 to a lesser extent). My parents also have a '93 E320 coupe (W124 with M104). Being an in-line six it is smooth, but again not as quiet as the M103 in our 300TE.
I will go along with the comments regarding the reliability of the M111. I have heard no complaints about them and they don't seem to suffer the often discussed problems of the M102, M103 and M104.
Comparing chassis, I would say the W124 for space, comfort and old-fashioned MB build quality, and the W202 for the modern features. Comparing engines, the M111 for reliability and fuel economy, the M103 for smoothness, quietness and ease of servicing, and the M104 for its power.
It really comes down to personal preferences.
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.