From its sculpted bonnet and quad headlights to its broad, low stance, the XJR shouts high performance. Although Jaguar was locking itself into a retro-led future during this era, the 322bhp XJR proved that a traditionally styled saloon can still look purposeful, just like the Mk2 3.8 did back in the 1960s.

The 1994 XJR was actually a development of the 1986 XJ40, an oft-maligned car that combined conservative exterior styling with a ‘Tokyo by night’ dashboard that got the traditionalists tutting. Yet it was still a teriffic drive and, once developed and greatly improved into the stylish X300, it leapt in both quality and desirability. The supercharged XJR sat at the top of the range, and was a great commercial success.

Central to the XJR’s appeal were its supercharged performance and soundtrack. With a top speed of 155mph and 0-60mph in 5.9sec, it had genuine supercar pace and addictive supercharger whine, yet it could still cosset its occupants as only a Jaguar could. Most importantly, it wasn’t – and isn’t – flash in the way of its German and Japanese rivals. 

In 1997, the six-cylinder X300 was replaced by the V8-powered X308, boosting the XJR’s power to 370bhp. The later car has a similarly Jekyll and Hyde character, smoother when wafting, punchier when going for it, yet it’s still very much an old-school Jaguar.

Both versions are fabulous for drivers and passengers, and their values are certainly going to rise in the long term.

You can buy a six-cylinder XJR for a little over a grand, but you wouldn’t want to. As Nene Jag Specialists’ owner Clive Kirton (above) says: ‘You will end up spending more again just getting the car into shape. Buy the best you can, then budget for about £1500 for unforeseen issues.’

Six-cylinder cars are cheaper because they’re older, but in many ways are better than the V8. Expect to pay £4000-5000 (more for the absolute best) for a car that’s been loved with a full specialist service history. 

Only six-cylinders had the option of manual transmission, which now commands a premium, but experts say the automatic is the better car. 

£7000-8000 will buy a V8 you would actually want: a straight car without issues. The run-out XJR100 models are particularly sought after now, and most likely to start appreciating first. Prices are set to rise in the longer term, but only once the rougher cars are out of the system.

Forget notions of unreliable Jags when you’re looking for an XJR. The six-cylinder car is much more dependable than the previous-generation XJ40 and, in many ways, less troublesome than the V8 car that followed it.

The six-cylinder AJ16 engine is fundamentally sound aside from the odd misfire, usually down to a failing coil pack. Unlike earlier power units, it rarely leaks oil. 

The V8 car suffers from more niggles, although the premature bore-wear that afflicted the Nikasil cylinder-lining of ’97 and ’98 cars is rare now, because most engines were changed under warranty. You can spot an affected car by its high oil consumption. 

Of major concern is that the V8’s mechanical refinement can mask problems. ‘A car with a worn engine could keep on going, sometimes for years,’ Clive says. ‘A lot of problems such as the timing chain tensioners, water pumps, sticking thermostats and oil leaks were down to poor design.’ There are also issues with the cooling system: its hoses perish over time, and you should keep your eye on the temperature gauge while driving because sticking thermostats cause overheating.

‘The standard XJs have a reputation for unreliable automatic gearboxes,’ says Clive, ‘but the XJR has a Mercedes-Benz item, which is as good as gold.’ 

Suspension bushes tend to need replacing at 50,000-60,000 miles, which manifests itself as a soggy feel at the wheel. Other than that, you might find rusty rear arches and scabs around the sills, but it’s generally best to walk away from these cars.

Another potential area for concern is the air conditioning – if it’s failed, it’s rarely because it needs a re-gas, but more likely to be a blown condenser or failed compressor. There can also be problems with the heating system’s electric pump – and that can be expensive; figure on paying £300-500. As for the Eaton supercharger, problems are few and far between. Clive has never needed to change one.

Whichever XJR you choose, you’re looking at a terrific driver’s car with plenty of road presence and performance. The neo-classical – some say retro – style of the XJR divides opinion, but undoubtedly will make it age-resistant as the years go by and will ensure it makes a smooth and natural transition from used car status to classic.

The most accomplished XJR dynamically is the V8 (although you might want to avoid the XJR100, which suffers from a less restful ride thanks to its larger wheels). It is effortless and comfortable, and rewards its owner like few other cars at the price. But the bulletproof nature of the six-cylinder X300 might make for a more restful night’s sleep. That reason alone makes it the wisest choice as a classic buy.