It suits experienced drivers who want something sharper than an ordinary fast car, and people who understand tuning and want to see what the tuner did to a factory M5. Of the three M5s on the Masons car hire list, it is the only modified one. Compared with the factory M5 Competition it is louder and has carbon-ceramic brakes, yet it keeps five seats and four doors.

What the M5 Manhart is good for

Most often it is a gift. A partner, father or friend gets a day with the car for their birthday: they collect the M5 in Prague in the morning, ask to be shown the driving modes at handover and return it in the evening. The gift works best when the recipient knows the date in advance and can take the day off. The best months are May to September, with dry roads and enough daylight for a long day.

The second scenario is a trip for two enthusiasts. One drives; the other listens to the downpipe exhaust, inspects the carbon-ceramic brakes behind the wheels at every stop and compares the car with what they know from forums and videos. For a pair like that, the Manhart means more than any factory version, because the work done on it can be seen and heard.

The third option is one long day on the road: leave at seven, take the motorway out of Prague, then the back roads of the Vysočina region, lunch in a small town and home before dark. The M seats with Merino leather stay comfortable after six hours at the wheel, and the head-up display keeps navigation in your line of sight.

In practice: seats, luggage and drive

The M5 Manhart is a full-size saloon with five seats and four doors. Two adults sit comfortably in the back, a third for a shorter trip, and the boot takes luggage for four for a weekend. Passengers do have to make peace with the exhaust, though: under acceleration it is louder in the cabin than in the factory M5, and on a long journey some find it tiring. The front M seats hold you well in corners, and the M1 and M2 buttons on the steering wheel store two set-ups, say a calm one for town and a sharper one for country roads.

M xDrive all-wheel drive puts the power down in the rain or on cold morning tarmac. It is usable in winter, but at its best in the dry. Under the bonnet is a petrol V8 with two turbochargers, rated at 720 hp after the upgrade according to the fleet data. The carbon-ceramic brakes may squeal when cold or damp; this is normal and does not affect braking. The saloon is long, so look for wider spaces in Prague's historic centre and older garages. Driven briskly, it uses a lot of fuel, so plan a stop about halfway round a full-day loop.

Where to take the M5 Manhart from Prague

For a full-day loop, head to the Žďárské vrchy hills on the border of Bohemia and Moravia, about 2 hours from Prague. The D1 motorway takes you to the Vysočina region, then minor roads lead through forests, past ponds and over hills, where weekday traffic is light and long, sweeping bends let you drive smoothly without hurrying. All-wheel drive helps on forest sections that stay damp long after rain. The first stop is Žďár nad Sázavou and the pilgrimage church on Zelená hora, a UNESCO site a few minutes' walk from the car park. Then carry on to Nové Město na Moravě for lunch, and in the afternoon stretch your legs at the Devět skal rock viewpoint.

M5 Manhart or BMW M5 Competition?

Both M5s share the same saloon body, all-wheel drive, five seats and four doors. The blue factory M5 Competition is calmer and quieter, so it is better for a long trip with family or business partners, to the Alps for instance. The Manhart is for a day that is mainly about driving: a gift, a trip with a fellow enthusiast or a loop of back roads. If your passengers want to sleep or make calls on the way, take the factory car. If you are driving and the experience is the reason for the hire, take the Manhart.