Road Test: Mercedes-Benz CLA Class CLA 45 4Matic 4dr Tip Auto

There's another new AMG, and, if you're an AMG fan, that's the one I'd go and read about first. The A45 AMG has a bit more about it than the CLA45 AMG. Not least because it's a more understandable car: a hot hatch, in the mould of the Audi RS3. We get that. Even AMG boss Ola Källenius freely admitted that it wasn't yet sure exactly who the CLA AMG customer is. AMG might even make a few tweaks depending on buyer feedback.

Here's the gist of it. The CLA is a more mature proposition than the A, so, for that reason, the suspension has been toned down fractionally, with marginally softer spring and damper settings on all four wheels. It also has a quieter exhaust, as they expect passengers will want a calmer experience in the back seats.

It's the first time AMG has played with a four-cylinder motor in its 45-year history. By bolting on a big turbo, it's got an amount of power we haven't seen since the days of those Mitsubishi Lancer FQ models: 354bhp and 332lb ft of torque from 2,250-5,000rpm. Turbos are good for power, but they also strangle induction noise and character. AMG has proved with the E63 that this can be overcome, but not here. It feels too plain and too placid to be an AMG. That may be why it doesn't feel that fast. Shorter gear ratios above third would help improve sprinting ability. The £510 Performance exhaust is a must-tick option - many more pops and crackles to remind you that you are driving something exciting.

You can work out why AMG has opted for long gearing - not to mention a 4wd system that decouples the rear wheels until traction is lost up front. It achieves 40.9mpg on the combined cycle and returns 161g/km of CO2. Better figures than an EcoBoost Ford Focus ST, which has 100bhp and 223kg less to deal with (the 1,585kg CLA is a proper porker). That much power with that much efficiency is a remarkable achievement.

And the CLA is no disaster around corners. Being four-wheel drive, and with the ability to send no more than 50 per cent of torque to the rear wheels, the handling characteristics are more closely aligned to the Audi RS3 than to the BMW M135i. But it resists understeer remarkably well, has colossal grip, superb body control and chassis composure, accurate steering and zero torque-steer. It's rapid and secure, but, by the same measure, is not a very interactive experience. And the cabin is a bit plain. And the styling is curious. I'm not yet sure what this car is trying to be. But that's OK - neither is AMG.