Why the comparison?
It didn't take a brain storming session to come up with this particular comparison test. As certain as night follows day and autumn moves into winter, high-performance Audis and BMWs will be pitted against each other. As far as enthusiasts are concerned, it was a fairly one-sided affair in the past, with BMW's M-models being laughably more rewarding to steer than their four-wheel drive arch enemies from Audi. That all changed with the introduction of the Audi RS4, one of the very best-to-drive cars to ever come from Ingolstadt.
Even BMW devotees had to admit that the battle between the E46 M3 and the RS4 saloon was a closely fought one, especially as the RS4 was launched towards the end of the former's life cycle. Now tables are turned and BMW's all-new M3 is finally on sale globally, just as the RS4 is being sent out to pasture. It's as compelling a comparison as ever though.
How are they similar?
Take a good long look at the technical specifications of these cars and you'll have to search for any major differences. Both use high-revving V8 engines of about 4.0-litre capacity to produce an identical 414bhp. The Audi's unit uses its extra 200cc of swept volume to belt out a little more torque, but the M3 counters by producing more of its torque more of the time. Thanks to nigh on identical kerb weights they're inseparable against the clock too, both scorching off the line and slamming through the 62mph mark 4.8 seconds later.
Those are the facts. In less tangible terms, both the M3 and RS4 represent the top of their respective model ranges, but more than that, they are the halo models, a way for the companies to link their regular products to their motorsport efforts. Enthusiasts will get as excited about these cars as they will any supercar.
How do they differ?
Obviously the body style varies significantly here, with the RS4 also available in Cabriolet and Avant versions. Saying that, BMW has already revealed details of its new four-door M3 and we are certain there will be a Convertible version, though no Touring model. However, the body style is fairly irrelevant to most buyers of this sort of car. Sure, if you have to fit in the family you are unlikely to opt for the M3 Coupé, but how these cars drive and perform are deciding factors in their purchase.
On that note, the most fundamental difference between the M3 and RS4 is the axles through which they direct their power. BMW is sticking with its rear-drive layout while Audi utilises quattro four-wheel drive, albeit with more torque sent to the rear wheels than ever before. This is the key distinction and a point that will divide buyers.
So which one would we have?
This is such a tightly fought contest that it's difficult to answer the question firmly in one way or another. There is very little difference between the cars in terms of performance, excitement or ability. The BMW does, however, offer a broader range of options for the keen driver, though the Audi is almost as good to drive. They both sound fantastic and even though the Audi is at the end of its life, it still cuts the mustard in terms of image and styling. In fact, it's the most extrovert in appearance. However, if pushed into a corner to decide between these cars as a new purchase then it would have to be the M3. It delivers a fraction more driver involvement and the fact that it's the newer car will make a big difference when it comes to resale value.
Shane O' Donoghue