As far as De La Soul were concerned back in their 1990s heyday, three was The Magic Number. Wind the clock on to today and, for me, 900 has taken on a similar sort of magical significance.

The similarity between the hip-hop band and me ends there, but I’m convinced I can reach 900 miles on a tank of fuel in our Peugeot 508 long-termer.

The last two fill-ups have indicated that it’s not an impossible feat – I’ve travelled 876.1 miles and 848.1 miles (56.1mpg and 57.9mpg) respectively before the fuel light has come on and my nerve has broken.

The latest fill-up has given me the most hope as, although I was still 52 miles away, I could only squeeze 66.62 litres in, meaning there was still more than a gallon left in the 508’s enormous 72-litre tank. I’m no mathematician but, by my sums, this would have been enough to break the 900-mile barrier.

Much of my driving is suited to achieving decent fuel economy - reasonably long, steady journeys, often travelling at 40mph behind supermarket lorries – but to get just above the official figure of 56.7mpg speaks volumes for how capable the 508 is.

The economy has been just one of the highlights since taking on the 508 after its trip back to Peugeot for some minor glitches to be repaired (see last report).

As someone who ran a 407 SW for a short while, perhaps the most striking feeling is just the size of the leap forward Peugeot has made in the upper-medium sector.

I liked the 407’s comfortable ride, but the 508 improves on this – and is much better in every other regard too.

Perhaps the biggest improvement has been in the cabin, where the advances in quality and design has given the saloon a genuine premium-car feel. Durability seems good too – after 12,000 miles the surfaces and textures still look and feel fresh, with no hints of any squeaks or aging whatsoever.

The start of my time with the 508 also coincided with the worse of the weather this winter so far but, thanks to the Michelin cold-weather tyres fitted to the Peugeot, this proved no hardship at all.

The tyres were supplied by ATS Euromaster and fitted in October 2011 by a mobile fitter at our office, but the relatively mild and dry winter until recently gave us little opportunity to feel the difference compared with standard tyres.

The extra grip was surprisingly noticeable – as an example, near my home there is a hill which, over the years, I and hundreds of cars have slithered up and down with difficulty at the slightest hint of snow or ice. This time, however, it was negotiated easily and safely, with no loss of traction at all.

Very impressive indeed – much like our experience with the 508 so far.

By Andrew Ryan