BMW 4-Series vs Merc C-Coupe vs Audi A5

Make 'em low and streaky. Whether it's a saloon, estate or hatchback, that's the brief these days. And car designers will chop off boot space or headroom with the casual flick of a pen, in search of a sexier line or two. Whack the word ‘coupe' on the back, and, bingo, you have yourself a sale. All of which means the coupe is no longer just a coupe. It could be a sloping crossover. Or a cropped SUV. Which may explain why, in order to avoid confusion - and give the proper koop its identity back - BMW has dropped the term completely. Want a two-door 3-Series? That'll be a 4-Series to you, sir.

Words: Dan Read
Pictures: Joe Windsor-Williams

This feature was originally published in the November 2013 issue of Top Gear magazine

It's arriving in showrooms as we speak, so we've gathered some opposition to see how it gets on. Specifically Germans. More specifically, the Audi A5 and Mercedes-Benz C-Class Coupe. Despite a recent refresh, the A5 is approaching retirement, while the C Coupe - which does exactly what it says on the badge - is only two years old. We've chosen the four-cylinder diesels, which keep them within reach of crunched salaries. That's just over 30 grand for starters, though the models we have here come in a variety of trims: an AMG styling/suspension pack for the Merc and a similar S line treatment for the Audi. The 420d is a base SE, though it does have optional M Sport adaptive ride. Those, plus a generous spray of other extras, bring them all closer to £40k.

Unencumbered by do-it-all briefs, they all have a licence to look good: the BMW, low and stretched; the Audi, steely and industrial; the Merc, poised and taut. The 4-Series - in this trim - makes do with less tinsel than the others, and the lower front bumper is filled with black plastic inserts, which could be improved with a slight upgrade. Better to invest in the visual treats, rather than the internet comms package or other costly extras buried in the long options list, which add around £8k to this one. More on that later.

The BMW is the longest car, at most risk from car-park dents as you squeeze in and out - a point exaggerated when you open the lengthy door and get inside, whereupon a robo-arm passes the seatbelt from over your shoulder. The cabin is otherwise familiar if you've spent much time in a new 3-Series. It's unfussy, uncluttered and the metal inserts are cold to the touch. The steering wheel is round. There's a proper handbrake. And the widescreen satnav display renders landmarks and even nondescript buildings in 3D, which makes navigation more like a game of SimCity.

The front seats could give you more of a squeeze, as could the two in the back. Same deal in the Audi. The Mercedes has them both licked on this, with buckety front seats and two moulded rears, which make the most of the four-seat layout. But after a while, you begin to appreciate BMW's puritan approach - you sit low, steering wheel just where you want it, head-up display keeping you focused and centred. Spend some time in the Audi, with your legs at 20 degrees to your hips in order to meet the offset pedals, and you'll be begging for the Beemer again.

Pop the 4-Series into Sport mode (part of the £750 M Sport suspension option), and it feels instantly attentive. Whether you're making a tight turn or pushing it through a fast corner, the nose always feels in sync with your wrists. It smooths over cracks and lumps, most probably helped by the moderate 18-inch alloys on this car, and rarely loses its temper when the road bucks or ripples. Some may say the electric steering relies on artifice, but you could argue that it only amplifies the mechanical stuff going on underneath. Perhaps the only let down is the slightly gristly gearbox, which requires considered placement to avoid fluffed shifts.

Where the BMW brightens up the driving experience, the A5 falls on old Audi habits and dulls things down. You sense that the steering - also electric - can't really be bothered unless you ask firmly. The 19-inch wheels and hard springs bosh into speed bumps with no regard for their own well-being, the pay-off for which would usually be increased control in corners, but you never really feel the benefit. We'd also highly recommend upgrading to a quattro system - this one's only front-wheel drive, and it feels like it could use an extra pair of hands. On the upside, it has the cleanest gearshift.

The Merc has the only hydraulic steering, and although it lacks the BMW's immediacy, it takes on a pleasing weight when loaded. Like the BMW, it has active suspension, although the car judges the mood for itself, so there's nothing for the driver to toggle. And it does a pretty good job, feeling firm yet comfortable, as if riding on a bed of expensive memory foam. You rarely feel any whacks - again, thank the 18s - and it's almost always well behaved, no matter what sort of road rolls beneath it. At 1,630kg, it's the heaviest car here by over 150kg, but also the most compact (though the blind spot is a pain at tight junctions). In many ways, it's like a decent hot hatch, with the bonus of rear-wheel drive.

And so to the engines. These four-cylinder diesels may never rattle our thrill-o-meter, though we can judge them by more sensible criteria. The BMW is the most powerful, but also the least torquey. Having said that, it delivers its muscle from as low as 1,250rpm, making it the most versatile one here. It's also the fastest, reaching 62mph a good half-a-second quicker than the other two, helped by the fact that, overall, it's the lightest of the three. And it lands a solid blow on the others at the pumps, achieving mid-60s mpg on our gentle motorway cruise, which - for once - is almost bang-on the manufacturer's extra-urban claim.

The A5's 2.0-litre TDI isn't far behind, but you'll have to work more diligently to get close to Audi's quoted 60.1mpg average. However, it does get on with things quietly, blending into the background more successfully than the Merc's or BMW's. This is immediately spoilt by the road noise thrown up by the big alloys. Seriously, avoid these wheels, no matter how much you like their looks. An extra inch of air and rubber would make for a more pleasant life on board, and help make the most of the crystal-clear Bang & Olufsen stereo, should you tick that rather costly box. You wouldn't spoil your home hi-fi by putting the blender on, so why put up with such distortions in the car?

The Merc has the worst economy, for which we can partly blame the automatic gearbox (a plain old torque-converter, rather than a dual-clutcher). It holds onto gears where cleverer 'boxes shift up, and even in manual mode - when you take control with flappy paddles - it doesn't like being told what to do, smudging shifts when you want a crisp change. At least there's an extra 200cc and a chunk more torque than the Audi and BMW, which helps pull you out of bother when you're in fourth but want third. It's also the noisiest engine here, and needs to learn some culture in order to worry the 4-Series.

Of course, silkier petrol engines with more cylinders are available for all three cars. So are more complicated gearboxes, including a lovely eight-speeder for the 4-Series. But upping the mechanical specs pushes the basic prices skyward, and that's not what this test is about. Besides, all three of these cars provide the ingredients for much hotter and hairier versions, from the C63 Black to the RS5 and - eventually - the M4, which means there's an even fightier test coming up sometime soon...

To make the most sense of these cars at this price, the key is to get your options right. It'd be easy to blow money on extras - up to 10 grand if you're not careful - without greatly improving the fundamental experience. We're not suggesting you skimp completely, and some options do float to the top: the Merc's sound system is almost seismic, and the BMW's infotainment upgrade is a no-brainer. And an A5 with four-wheel drive, adaptive ride and smaller alloy wheels would feel like a very different car from the version we've tried here. Although ultimately, not one we'd be inclined to choose over the other two.

Which leaves us with the Merc and BMW. The Merc is genuinely tempting and, if you're running towards the showroom right now, we won't yank you back. For those of you still reading, well done. In this configuration, the 4-Series may look a touch underwhelming in places - especially around the mouth - but spend an extra £1,500 for the Sport trim, and you're laughing. Its spread of talents is borderline freaky. It's the fastest and the most rewarding. And while you may secretly weep at the thought of a humdrum diesel in your slinky coupe, you'll cheer up when you see the fuel gauge clinging stubbornly to the full end...