The performance of this car is excellent especially when considering how inexpensive it was to purchase used (in very good condition.) This classic BMW is very agile, and the factory M-Technik sport suspension (which is standard on the S models) allows it to corner in a very flat manner with minimal body roll. The suspension is not plush however, it is tuned for performance. The car is also very fast for the money (0-100km/h in 7.4 seconds with a maximum speed of 215km/h.) Throttle response is excellent and the engine shows no hesitation whatsoever. The engine loves to rev. The rear-wheel drive layout is excellent in dry and rainy weather, but it does requires you to remain focused while driving in snow.
The car does not leak any oil (or any other fluids.)
The exterior of the vehicle is representative of the styling in Germany during the period (1984-1990.) The design is timeless. The car's body is lean, taut, functional and businesslike. Exterior rust is non-existent. Fit and finish is on-par with cars ten years newer. Everything is well engineered.
The interior is ergonomic and very business-like, with everything placed where it should be. The sport seats (which are based on a Recaro design) are very good, with lots of side bolstering. The temperature gauge is temperamental during start up, but it stabilizes and gives a correct reading once the engine warms up (I haven't diagnosed the problem.)
The steering is direct and well weighted. It is not watered down whatsoever.
The most startling thing about this car to me is the visibility from the driver's seat. Front, side and rear visibility is incredible, most likely due to the large greenhouse and low door line. The blind spots in this vehicle are minutely small.
The manual shifter is unfortunately sloppy and has a lot of excess play and travel, but this is due to worn-out plastic bushings. In original condition, the shifter is faultless. Replacement of these parts costs a reasonable amount.
The clutch is great, and it is weighted nicely (it doesn't feel like you're stepping on a marshmallow.) It also has great pedal feel; you can tell exactly where the clutch engages and disengages.
The timing belt (it is actually a belt, not a chain) must be replaced every 60,000km, or you risk serious damage to your engine. The cost of replacement is about $280 Canadian at my local BMW dealership. It would most likely cost less at an independent garage. This is the car's only serious issue.
If you're looking for an inexpensive, reliable, agile, classic German sports sedan, this is your best bet.