Launch colours are important. Often the cars seen in the first adverts and press drives will be the same shade, and, as parents always say, you only get one chance at a first impression. Sometimes it's great, like the Chicane Grey for the McLaren 675LT; sometimes it's not so great, like the lemony-gold Solaris for the McLaren 675LT Spider. And then sometimes a launch colour becomes so inextricably linked with a brand that special editions are still being made 30 years after the event.

Nogaro Blue is that colour for Audi. The RS2's paint was actually RS Blau pearl effect - Nogaro Blue was a different colour was probably best known for the RS cars, of which this is of course one. That said, show anyone bar the most knowledgeable a blue RS2 nowadays and you know what they'll call it, as 'Nogaro' is a bit catchier than plain old 'RS'. Audi's subsequent special edition RS4s, RS6s and even TTs surely wouldn't have been commissioned if it was the prosaic name that caught on. And they've been quite cool - so Nogaro Blue, however inaccurately it may have been used, is fine by us.

This RS4 is definitely Nogaro, and looks great for it. It's odd to think of a colour now so highly prized being rare, but it's hard now to recall having seen another one. Typically with the B5 you see silver and black cars, maybe the odd yellow one, so it's a real treat to see such a memorable shade this well presented. More than 20 years after launch it's notable that the colour is perhaps the most attention-grabbing aspect of this RS Audi; the wheels would have looked enormous at the end turn of the century, and they were probably chunky exhaust pipes once upon a time, but most wouldn't give this old A4 another look.

Like the first RS6, much of what defines an RS4 today can be seen in the very first one. This had a 2.7-litre twin-turbo V6; the 2022 configuration is the same, and only 200cc bigger. And while it isn't necessarily the icon the RS2 is, the first RS4 has been quietly appreciating of late. Its predecessor's rise will have helped that, as will the model's comparative rarity, but the styling - in Nogaro Blue or otherwise - will certainly have played its part. There's far too much glass here on show to be called modern, but given the RS4 was based on a car launched in 1994 it's aged tremendously well.

It helps, of course, that this one is a stunning example. Just 26,000 miles for a car like this - i.e., one explicitly designed to ferry people and stuff far away at high speed - really is remarkable, and the condition is commensurate with that number. To have Nogaro Blue survive this well is one thing; for Silver Silk leather to still look like this after 21 years is quite another. This one is from a collection, so presumably will have lived a gentle life, yet it scrubs up superbly well even allowing for that.

Given the condition, and the selling dealer asking £40k for it, this RS4 is probably destined for another collection rather than regular use as a modern classic with hot hatch humbling performance. But then that's also why a B5 RS4 of any kind is so great: at its core is an A4 estate, yet thanks in no small part to some Cosworth input, it's a Nogaro Blue Audi Avant deemed worthy of preservation. Quite right, too.

SPECIFICATION | AUDI RS4 (B5)

Engine: 2,671cc V6, twin-turbo
Transmission: 6-speed manual, 4-wheel drive
Power (hp): 380@6,100rpm
Torque (lb ft): 324@2,500rpm
MPG: 23.4 (NEDC combined)
CO2: 288g/km
First registered: 2001
Recorded mileage: 26,000
Price new: £46,500
Yours for: £39,980

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