I can't honestly answer the question about the timing chain set up on the 177 hp 6 cylinder W126 engine, but have heard that the timing chain/tensioner/guide rail 100k mile change doesn't seem to be quite as imperative and urgent as on the V8 W126ers

Beyond that, the close coupled W126 short wheelbase SE is a remarkably agile handler for its size, more sexy looking than the SEL and the gargantuan W140 cars you are looking at.

Moreover, with the axle ratio it has, the 300SE is suprisingly peppy in city traffic, and while it is slow in merging and passing compared to the 560SEL/SEC, once at highway speed, you can't tell the difference, they are all great highway cruisers, able to reel in large chunks of macadam in a single stretch.

Of all of them, the 300SE will be the best on gas consumption, a fair thing to consider , in these out of joint times.

Buy the 300SE, pending a PPI

Some W126 tips for buyers can be found at this place, I co wrote it in 1998 with the 560SEC coupes in mind, but a lot applies to the 300SE also.

www.mbcoupes.com (buyers guide)

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)