It’s mechanically near-identical to the four-door BMW M3, but the low-slung M4 Competition is clearly not as practical as the saloon. The 445-litre boot is 35 litres smaller, but it’s well-shaped and features a decent-sized opening. The same can’t be said of the convertible, which features a 370-litre capacity with the roof up, and a stingy 220-litre layout when it’s lowered.

Both the coupe and convertible have the same sloping rooflines, so anyone over six-foot tall will have their head rubbing against the roof. Still, there’s plenty of legroom in the back, plus the two individual seats are supremely supportive.

Obviously, those back seats are more difficult to access than in the M3 because of the two-door layout, and you only get two individual seats, rather than a three-seat bench. Even so, the M4 is still practical for a coupe, particularly when compared to similarly priced two-seat rivals such as the Porsche Cayman. For instance, the BMW can realistically be used as a daily driver and occasional family transport.

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Size

In terms of its external dimensions, the M4 Competition is a little larger than the standard 4 Series Coupe. The extended front and rear track mean its 55mm wider, while the aggressively styled front and rear bumpers add 33mm to the car's overall length. Surprisingly, the M4 is actually 6mm taller than the run-of-the-mill 4 Series.

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2022 Fiat

500

12,924 milesManualPetrol1.0L

Cash £10,400

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2026 BMW

4 Series

26,030 milesAutomaticPetrol2.0L

Cash £25,997

View 4 Series

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2025 Audi

A5 Sportback

37,025 milesAutomaticDiesel2.0L

Cash £25,197

View A5 Sportback

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2026 BMW

25,438 milesAutomaticElectric

Cash £29,197

View i4

The M4's two-door body isn't ideal for family use, but the doors open wide and the front seats tilt and slide forward to ease access to the rear bench. And, while the M4 is marketed as a coupe, it has a traditional 'three-box' saloon design, meaning you get a decent glass area with good visibility. This isn't quite the case with the Convertible, which features a folding hardtop with thick C-pillars, which hinder your over-the-shoulder vision.

Legroom, headroom & passenger space

Despite what you might expect, given its Coupe name, the M4 is surprisingly spacious and practical. Unlike other 4 Series models, the M4 is a strict four-seater, with the rear bench divided into two, bolstered chairs. Still, headroom is good despite the sloping roofline and there's a decent amount of legroom. It's worth noting that the limited-run GTS model swapped the rear seats for a bright orange roll cage.

Convertible models aren't quite as spacious in the rear, as the hood mechanism eats into shoulder and elbow room. Still, while its cosier than the Coupe, there's still enough space for two adults to sit in reasonable comfort. And while the thick C-Pillars make it feel a little claustrophobic with the roof in place, it's far airer than the fabric roofed Audi S5 Cabriolet.

Up front there's lots of room to lounge around in, while the wide range of seat and wheel adjustment makes it easy to get comfortable behind the wheel. Importantly for a high-performance machine, the M4's seat can be set very low which helps you feel part of the car when driving quickly.

There's plenty of handy storage for odds and ends, including a large glovebox, deep door bins with integrated cupholders and useful trinket tray ahead of the gearlever. There's also a lidded cubby between the front seats, although it's quite shallow.

Boot

Like the standard 4 Series, the M4 Competition has a slightly smaller boot than the four-door 3 Series on which it's based; and, perhaps more importantly, its 445-litre capacity is 10 litres down on the Audi RS5's load bay. That said, the M4 benefits from a large opening, and the load area is well shaped wirth few awkward intrusions.

Sadly the same can't be said for the Convertible, which gets a 370-litre capacity with the roof raised. However, lower the hood and the available space shrinks to 220 litres, which is less than many city cars. As a result, you'll have to travel light if you want to take a trip four-up and experience some wind-in-the-hair thrills.