I own 2 w124's - 94 E420 and a 94 E320 Coupe. My advice is find a 94-95 w124 with less than 100k miles and you will have a good automobile for many years to come. Be aware of the wiring harness and head gasket fixes, but after that it should be smooth sailing for many miles with routine maintenance.
I truly believe the w124, years 1994-95, were the best vehicles MB built.
After that quality control, over-engineering and complicated electronics began to takes it's toll. Good luck in your decision, let us know what you decide!