BMW X3 M Competition
Why 5.9: The first X3 built by M GmbH rather than trimmed to look like one: the S58 straight six that went on to power the G80 M3, 503 hp in Competition form, 0–100 km/h in 3.7 seconds. It is also two tonnes on a school run, and it rides like the engineers were angry about that.
Layout
Natural habitat
Ride comfort
Sound
The S58 is a hard-edged straight-six on paper and will crackle on the overrun. In an SUV it arrives through twin turbos, extra insulation and speaker augmentation, so what reaches the cabin is a manufactured impression of the M3 rather than the thing itself.
6-cylinder · turbocharged · 7,200 rpm redline · rated 4.6 / 10 for engine sound
Market value
Median asking price, good condition · €71k (2020) → €46k (2026), trending down · illustrative data
Child seats · ISOFIX
Two ISOFIX positions on the outer rear seats, the outer pair being the ones the standard covers.
The rear anchors are the supported route — the manual points child seats there, and front-passenger ISOFIX is the exception rather than the rule. A belt-mounted seat up front needs the airbag off, and cars with a rear row don't always fit a deactivation switch, precisely because the rear seats exist.
Derived from production years and seating layout, not a per-car source. ISOFIX was standardised as ISO 13216 in 1997, required on new EU model types from 2011 and on all new EU cars from 2014.
The long version
M GmbH had let the X5 M and X6 M exist since 2009, but the X3 M was the first time the compact SUV got the full treatment rather than an M Performance badge. The engine is the significant part: the S58 3.0-litre twin-turbo six made its production debut here, six months before the G80 M3, with a closed-deck block, a 3D-printed cylinder head core and 600 Nm from 2,600 rpm. In Competition trim it makes 503 hp and the car will out-accelerate almost anything wearing a roof box. The rest is compromise. Suspension stiff enough to be uncomfortable on British roads, steering that reports almost nothing, and a kerb weight just under two tonnes that the chassis contains rather than disguises. Buyers treated it as what it is — a very fast family car — so the mileage is real and the depreciation is steep and orderly. BMW ended F97 production in 2024 without a direct replacement, handing the compact-SUV job to the electrified X3 M50.