Not sifooo lar, just happen to have owned both.
Ok, it's like this both are damn finely engineered cars by the germans. Both are probably the best examples from both marques. But it depends on what you expect from a car.
The Merc: Probably the best compact luxury saloon ever built. Offers factastic ride and built quality. Go for the late model 2.0 or 190e 2.6( same engine as the W124 260e sedan). The 2.6 is the best in terms of weight to power ratio. Handling is similar for both and is quite good for an 80's saloon. Typical Merc character of plenty of bodyroll but good grip! Easy to maintain, no specialist required, any half decent mechanic will do. No rust issues on models after 89 as they are galvanised.
However, the final drive on all variants of the 190e family is very dissapointing......3000rpm in top gear is 115km for the 2.0 and 120km for the 2.6. It's fine for urban driving but not enough for highway cruising.
Conclusion: Excellent value for money, frugal, well built, readily available parts and they are cheap! A great cruiser and projects a very favorable image for the driver.
The Bimmer: Best sports sedan from the era. Ergonomically superior but lacks the classy ambience of the merc. Trouble free motoring from the last model 318i M40 and the best choice for those seeking an introduction into the world of e30s. 325i is the choice for those with sporting intentions but please learn how to handle a rear wheel drive in advance! One of the best handling cars ever! PERIOD! Easy maintainence but need specialist attention to get the best out of the engines. Rust free after 89 (look for the plastic bumpered cars).
However, not as frugal to run as the other german and cosmetic parts can be hefty. Mechanical parts are cheap and readily available. The ride quality may not appeal to all due to it's sporting nature.
Conclusion: Best of the 80's motoring icons and still relevant today. In terms of drivability and dynamics it is examplary even by today's standards. Notty image for the owner though.....(not necessarily a bad thing....hehehehe)
THE BOTTOM LINE: comparing Mercs and Bimmers are like comparing apples and oranges, they are just not the same thing. Their design and engineering philosophies are on completey different paths. They are both very, very good cars and that's why I have both.
I'll take the 2.3 16V for its racing predigree..
