BMW added a Porsche-pounding performance version of its Z4 model when it revised the Roadster range earlier this year.
The M Power model can nip to 62mph in just five seconds, which is quicker than a Boxster.
Powered by a 3.2-litre engine producing 343bhp, the new range-topper is worth every penny of its £42,795 price tag because of its sheer performance prowess.
To match the prodigious power there are more powerful brakes, pin-sharp steering and improved aerodynamics courtesy of a lower front bumper and an eye-catching diffuser at the rear.
There are also four exhaust pipes, which not only ventilate the engine but give the car an even more purposeful look plus a delightfully throaty sound.
The rest of the range also received some subtle styling changes including new headlamps and different bumpers, grille, tail lights and rear spoiler.
There is a new 2.5-litre engine with 218bhp of power, which is significantly more than that of the previous car.
The same applies to the revised three-litre engine, with a power hike of 34bhp to a new high of 261bhp.
These engines come with the option of a six-speed automatic gearbox with steering wheel-mounted paddles for swift changes.
The 150bhp two-litre engine continues unchanged but the 170bhp 2.2-litre unit was dropped.
Completing the revised line-up is a new Sport version with 18-inch alloy wheels, leather sports seats and stiffer suspension.
In its latest guise the Z4 is a proper sports car, which the earlier Z3 never was.
Pick of the bunch is the M version, which goes as well as it looks and because of its prodigious performance is worth the dosh.
FAST FACTS
BMW Z4 M Roadster
Price: £42,795
Mechanical: 343bhp, 3,246cc, 6cyl petrol engine driving rear wheels via 6spd manual gearbox
Max speed: 155mph
0-62mph: 5 secs
Combined mpg: 23.3
Insurance group: 20
CO2 emissions: 292g/km
BiK rating: 35%
Warranty: 3yrs/ unlimited mileage, 3yrs paint, 12yrs anti-rust