I would be very, very, very suspecious of the new trans and the rebuilt suspension. It definitely denotes a hard driven car, as any rightminded owner of a 500E would treat his/her car.
The problem is that hard driven cars, especially big special edition V8s tend to be extremely expensive to mantain once they reach certain high mileage.
If you don't mind the huge repair bills, go for it. If you do, may a 400E or even an S420, softly driven by a suburban inhabitant would be a better choice.
S 320, 1998
E 320 T, 1995