I agree with my fellow Gopher, Zoonhollis, however, any automatic transmission is an expensive, inevitable repair.
A manual transmission gets a clutch every few thousand miles and keeps going. My 240D has 533,000 miles on the transmission, and has NEVER been apart.
Like anything else, the convenience(?) has a price. I not only enjoy driving a stick, but I like the rock solid reliability of a stick that's afforded to those who know how to drive one properly to make it last.
The MB automatic in the 123 cars shifted a little funny, but is a precision piece of machinery as Zoonhollis pointed out. The AT in your Chevy truck would probably cost somewhere between 25% To 50% as much to rebuild as an MB automatic. Of course, if you had that truck in Germany, the numbers may be reversed.
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in