My 300SE rides exactly as you describe. I really never have been impressed.

My 300D is smoother and feels more solid to be honest. Soaks up bumps around town and I feel less shudder/shock through the steering wheel. Both have rebuilt front ends.

My old 116 was smoother riding than either, and was the most solid of the three. Out-cornered both too.

Don't think I will buy another 126. Keeping my eyes peeled for a 450SEL or maybe a 280E, with a 5 speed. 210 and 140 too flashy and modern. I prefer frumpiness.

__________________
'90 300SE 298k
-300K and it gets put into retirement.
'80 300D 255k Purchased new by family in 1980.

Had a:
1973 220 (gas)
1980 300SD
1992 400E