Which boot is best?
Well, it’s a classic case of what you read on paper not necessarily translating into a real-world advantage. At 505 litres, the A4 (above) has the biggest boot in its class – 55 ahead of the Merc – though the tables are turned if you flip the seats, with the Audi mustering 1,510 to the C-Class’s 1,600 litres.
Y’see, the Benz is actually a more useful space. Its loading sill lip is tiny, so you can slide heavy stuff in easily, while the A4 has a step. And if you’re spending more time with the seats folded, the C250’s flatter load bay, greater hidden storage and one-touch folding seats out-boot the A4.
Another Star Trek cabin?
Up front, meanwhile, the A4 is, predictably, a pretty exquisite place to be. It’s minimalist without being annoying to operate, and its fit ’n’ finish would make Bentley sweat. As would the cruising peace – leagues quieter than the gruff Mercedes.
If any car can compete with the Audi’s delightful cockpit, it’s the little Merc with S-Class ambience. Trim isn’t as opulent here, and there’s a more classical, less industrial quality. Rejigged Comand system is confusing to operate.
Which will I have fun driving?
This 187bhp 2.0-litre TDI, joined to £1,530 of dual-clutch gearbox, fits the A4’s remit of being a polite, user-friendly but not especially emotive bit of kit. The stop-start system, insistent on killing revs as you roll to a stop, is a pain, and optional 19s hurt the ride. Audi’s power deficit is undetectable on the road.
The C250d couldn’t be a more different animal. The 2.1-litre diesel hates cold starts and its drone is ever-present so it’ll win no chauffeur awards, but steering weight is better judged, it rides more compliantly and it’s just that bit more balanced and keener to react when you hustle it. Good ol’ rear-wheel drive.
What are the must-have options?
For the Audi, S line (£1,500) buys the world’s most subtle body kit, Wembley-spec LED lights, 18in rims, with deletable sports suspension. Tech pack (£1,450) unlocks virtual dials, but with a big screen already atop the dash, and standard nav, do you need it?
Merc has also grown a pack mentality. This car has £2,795 of Premium+ pack which throws in fripperies you won’t miss (ambient lighting, voice control) and juicy stuff like a Burmester hi-fi, electric seats and keyless go. Beware the headroom-eating glass roof.
Though it has anonymous looks (not that that stops anyone buying Audis), and the boot isn’t as versatile as it should be, the A4 is a fab object, but not the consummate wagon. Still, it boasts a stunning Bauhaus cockpit, and it’s quieter than a church mouse’s funeral, which you’ll really appreciate on long trips.
The Mercedes however, has a big, easy-to-use boot, feels special inside too, and it has the edge as a driver’s car. Yes, the noisy engine can be sluggish, and the media/nav control is complex, but the C-Class retains the family estate crown.