To Neal's point I had an 87 SDL and a 95 S420 in the driveway at the same time. The 140 is so much more modern than the 126 that it's hard to believe they're one generation apart. Reliability aside, MB alienated a lot of the faithful by going the path of Lexus. To me it was a good move. Getting warm air out of the center vents and controlling the fan speed independently of air temperature matter to me. There are other features that just make sense... and some that don't like $20 halogen bulbs for the c-pillar reading lights. Of course you can't cast reliability aside for too long. Fortunately there's a growing amount of 140 info in the archives and websites like JimF's (thanks, Jim!) that you can keep a 140 running on a DIY basis. Now that they're about fully depreciated the handful willing and able to keep them going are going to have one heck of a ride.

Get as late a model year as you can afford. Particularly with the V8s. The coil-over-plug arrangement in the 96-up cars is much easier to deal and less arc prone than the dual distributor arrangement in the 92-95 cars. Not having the parking guide rods and power memory rearview mirror after 95 or 96 is disheartening but you'll get over it. The counterpoint is that the 722.4 4-speed AT is more robust than the early 722.6 5-speed AT. Whoever came up with second gear start should be deprived of his/her retirement pension but a tranny that works is better than a tranny that doesn't :/ AFAIK all S320s have some form of 5-speed AT.

Go for a LWB car. Even if you never sit in the back The S320 was available in LWB from 95. The 300SD/S350 was not available in the US in LWB.

I hear the fuel mileage of the S320 is respectable. My S420 got 15 city/20 highway.

Sixto