I'm not sure why you would want to trade for a later model of equivalent mileage, but here goes:
I have a 93 3.2, so I can't comment on the performance of the 2.8. The M103 (as well as the M104) has historically had head gasket problems...but at that mileage, it has probably been replaced at least once.
You do get a bit more luxury in the 93...they have the wood trim on the dashboard and door panels, absent on the 89-92 models.
A weak A/C may be a red flag though...the evaporator on these models are problematic, and replacement including labor can set you back as much as $2500!
These are solid cars, but have a tossable handling and feel, much like a car of much lighter weight. Just make sure you have a trusted mechanic do a thorough inspection. These are reliable cars, but if maintenance was anemic, then you will be chasing problems for awhile.
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car