That's right, the C280 is the same 2.8 liter M104 engine used in the 1993 300E 2.8, and just a smaller version of the 3.2 liter M104 engine used in the 93 300E 3.2, 94-95 E320, 96-97 E320, and 92-99 S320.
Therefore, you are going to have the same issues that all M104 engines have. The original head gasket design was bad, and you will experience an oil leak at the right rear corner (passenger side) of the head gasket. You can let it leak oil until it gets so bad that you're going to have to replace the head gasket. I just did mine at 137,500 miles. The new head gaskets have been redesigned and don't leak.
Also, all 93-95 C280's and 300E's / E320's have faulty engine wiring harnesses. Check and see if it's been replaced on the car you are thinking of buying. If it hasn't been done I wouldn't rule the car out, but just budget $800 in parts and labor to replace the engine wiring harness immediately.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".