I have in the past had numerous W123s when they weren’t old cars , 280E/CE/TE and more W124s than I could list .
In their day , W123s were certainly more robustly built than the W124 which followed , the mechanical build was heavier and W124s feel comparatively lightweight , especially the feel of door closure and other mechanical components like window mechanisms . W123s were also more solidly built than 190s , which are more on a par with W124s .
W123s are about a decade older than 124s and tended not to have as much equipment as the later cars , finding ones with air con , for example , will be that much harder , they are also a bit more costly to run , as I well remember when I transitioned from 123 to 124 : my last 123 was a late 280TE and I swapped it for an early 300TE , the 280TE was about 5 years old when I bought it , and the 300TE was less than 3 years old when I made the change , and still the current model . Still I concluded after that , that spending a lot more on what I considered to be a nearly new car really didn’t buy me a significantly better car as there was nothing wrong with the old one ; however the 280TE was a 20mpg car while the 300TE returned between 25-30mpg , and the M103 was much smoother and quieter than the M110 .
Both cars had 4 electric windows , 4 speed auto , and cruise . neither had air con , the 124 had electrically adjustable seats and an electric tilt/slide sunroof , the 123 had a manual , slide only sunroof ( electric was not an option on the estates ) , and manually adjustable seats . Cruise on a W123 used a vacuum diaphragm actuator while it was electric on the 124 , neither gave any trouble . Both cars had factory tow bars .
My 280CE used thermal , auto resetting fuses on the rear side windows , these would sometimes trip out and you just had to wait for them to cool and reset , the 230 and 300CE had the seat belt butlers which could be temperamental but never actually broke , and again electric seat adjustment. Seat backs on the coupes all had a vacuum locking mechanism which confused some MOT testers as they locked only with the engine running and doors closed .
The W124 all had , if not air con , a climate controlled heater system with sensors in the cabin at high and low levels to maintain a set temperature , while the W123 was a manual system where you just dialled a temperature on each side . Oh , American cars tend not to have separate heater controls for left and right , unlike everywhere else .
In case you’re considering them the earlier W115 ( 4 cyl ) and W114 ( 6 cyl ) cars that came before the W123 were excellent , and arguably better looking and built cars ( also the coupes are very stylish ) but again there ranged from 1968 to 1975 so are that much harder to find in good condition and tend to have less equipment again : my 1970 220/8 , which my dad bought new before passing it to me , had no central locking for example , all four windows were manual , but it did have geared front quarter lights , and it had steering column manual gear change ( which was just such a pleasure to use , as it was in my Ponton and my Fintail ) , oh and no sunroof , although that WAS an option . My 1975 280E on the other hand did have central locking , 4 electric windows , no sunroof but it had the 5 speed close ratio manual floorchange box ( it was a homologation special ) and 5 Fuchs ( Mexican hat ) alloy wheels and 185/70 HR14 tyres , compared to the 175SR14 s on the W115 .
W114/115 cars had quite taut and accurate handling ( they were extremely chuckable and easily put into , and recovered from , controllable 4 wheel drifts , W123s were all floaty and barge like ( engineered for the American market ) , so wouldn’t drive them too adventurously , but once the W124 series came out the sharper handling for the European market returned . W201s , which came out between the W123 and 124 ranges also had better , sharper handling , although the 2.6 with the extra weight of the 6 cylinder up front didn’t turn as sharply into corners as the 4 cylinder ones .
