I would suggest you to search this forum for posts from Nevada Jack and others who have had both cars.
On the other hand if you search the W140 forum, they would suggest W140 being a better choice (W123 guys feel it being better than your W124). Perhaps current W221 owners are fully objective here but since I doubt you could find past W221 owners who now have an older S, I don't see better options than the above. A lot of opinions anyway already available here (don't mind owners writing here some more).
I would suggest you to search this forum for posts from Nevada Jack and others who have had both cars.
On the other hand if you search the W140 forum, they would suggest W140 being a better choice (W123 guys feel it being better than your W124). Perhaps current W221 owners are fully objective here but since I doubt you could find past W221 owners who now have an older S, I don't see better options than the above. A lot of opinions anyway already available here (don't mind owners writing here some more).
I have a 2001 S500 (220) and a 1995 s500 (w140) and i pefer to drive the 140 over the 220 i feel like the king of the road when driving that thing.
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