Mercedes' rear-wheel drive W220 S-Class was introduced in mid-1998, and was not only lighter on its feet than its W140 predecessor, but also offered greater cabin space and debuted plenty of new technology during its production lifetime.
The first AMG version - the naturally-aspirated S55 AMG - launched in 2000, packing a 360hp 5.5-litre V8, with a healthy 391lb ft of torque, it could hit sixty in just 5.8 seconds. But buyers wanted even more. So a supercharger was added in time for the 2002 facelift, which also heralded the arrival of the world's first pre-emptive safety system - Pre-Safe. The W220 S-Class received an exterior refresh, whilst underneath the S55 Kompressor AMG now produced 500hp, plus a colossal 516lb ft of torque. Sixty arrived in a mere 4.6 seconds and other changes included enhanced brakes and wheels, plus Active Body Control to try to keep the handling and ride as restrained as possible.
If this S55 still wasn't potent enough for you then Mercedes introduced an even more powerful alternative too, the 2004 S65 AMG. Packing a twin-turbocharged V-12 which produced 612hp, the rear-wheel drive W220 S65 AMG remains an epic machine, even by today's extreme standards. It's specially modified five-speed automatic transmission was capable of handling the car's riotous 737lb ft of torque, enabling the S65 AMG to accelerate from walking pace to 150mph in one seamless push. Unlimited, the top speed was estimated at 200mph, and 0-62mph took just 4.3 seconds.
Officially the world's most powerful series-production saloon, Mercedes' Active Body Control system now worked even harder to keep things buckled down, adjusting spring and damper rates to limit pitch and dive, and reducing body-roll during hard cornering. Whilst in a straight line, owners have recorded quarter-mile drag times of around 11 seconds.
Despite this outrageous performance, both the S55 AMG and S65 AMG can be supremely quiet, comfortable and effortless to drive - even at 150mph. But what about buying and owning one? Well the W220 is certainly solidly built, but the electrics can present expensive problems with age, as can the dreaded tin worm. And there's a lot of trickery to potentially go wrong.
Compared to the facelifted versions, the early naturally-aspirated S55 AMG does feel a tad slow and there are very few examples left in the UK - so finding a good 'un won't be easy. "You could suffer huge repair bills and there aren't many good ones left," confirms Olly Stoner at Mercedes specialists Prestige Car Service. This view is backed up by Steve Dickens at experts Autoclass Garage MK: "The non-Kompressor W220 S55 seriously suffers from rust issues on bodywork and sills, and is under-powered and a bit gutless." Add in a reported risk of transmission problems, ignition switch and key failures and ABC system pump faults and ownership could prove an expensive prospect.
The later supercharged S55 AMG is a far better proposition. There are more around (215 were sold to UK buyers) it's a lot faster, the engine is a gem, and this facelifted W220 seems to suffer fewer problems. "Rust is not as much of an issue," Steve confirms. "But still look out for charge cooler pumps which can fail, sticking throttle valves and any issues with the Active Body Control system - like struts which are very expensive to replace."
It's also the most likely to become a future classic: "Low volumes mean that they will always be in demand," reports Robert Redman at trade gurus Glass's. "It's also a highly tunable vehicle, with better switchgear and most electrical foibles ironed out," enthuses Chet Sharma at Mercedes tuners CKS Performance.
The rare V12 S65 is more of an acquired taste, with just 17 UK examples ever selling. It's highly exclusive, delivers awesome performance and, if money for ongoing maintenance isn't an issue, could one day prove a highly desirable classic. But is best avoided otherwise. "Brakes are very expensive," Steve Dickens tells us. "And in addition, the engine mounts can fail, necessitating engine removal to replace them." Ouch! Olly Stoner doesn't pull his punches either: "Coil packs break as can the ABC suspension, so you're best to avoid the S65 AMG like the plague!"
Buy if: you fancy an exclusive AMG (rust-free S55 AMG Kompressor preferred)
Don't buy if: you're not prepared to spend big money on ongoing maintenance
We found: 2002 S55 AMG Kompressor Saloon, Black, full service history, 75k miles, £13,500
Price Guide
Poor: Under £13,000
Good: £13,000 to £18,000
A1: £18,000+
Special Editions: Extremely rare W220 S62 AMG V12 can fetch up to £25,000