Oxfordshire looks lovely. Acres of farmland ripple away on either side of the motorway, punctuated by stands of trees bearing the golden glow of late autumn. Constable himself could have applied the clouds that puff across the northern horizon.

The sky to the south is sliced up by jet trails, left behind by machines travelling nine times faster than mine. But ticking off the miles at one a minute is just fine with me — and the £5 I paid for the 120-mile coach ride between Birmingham and London is equally agreeable.

I am one of just 14 passengers on this 48-seat National Express coach. Yet it feels odd, because today is neither Christmas Day nor Boxing Day. I am a fiercely loyal National Express customer on a maximum of two days a year: 25 and 26 December. When the trains shut down, the coach company steps up to maintain essential services; on Christmas Day 2016, National Express is planning a 50 per cent increase in services, to 64 towns, cities and airports.

For the rest of the year, I am not one of the 50,000-plus people a day who step aboard a National Express coach. Partly they choose the bus because of price: fares tend to be lower than on trains whether booked in advance or on the day. Another big part of the appeal is a wealth of A-to-B journeys that can cover formidable distances across the land without the need to change.

In Grimsby and wish you were somewhere else? Can’t think why. But since you ask, at 7am each day a bus sets off for Westward Ho! in North Devon, via Cleethorpes, Lincoln and pretty much everywhere you can imagine.

Trains don’t do that. Cars can, but Angela and Ron White from Solihull, who I met just before they boarded the Birmingham-Bristol segment of the journey, prefer to let someone else do the driving on longer trips. They’re off to a festival in Weston-Super-Mare. “And when we arrive in Bristol, we can use our bus passes to get to Weston free,” says 70-year-old-but-looks-much-younger Angela.

Older travellers like National Express. The challenge for Vinay Parmar, the customer experience director, is to tempt a new generation of travellers on board.

“We have to transform passengers’ perceptions of what a coach is,” he told me at the firm’s HQ above Birmingham Coach Station.

“For many people, their last journey was on a school trip, which they didn’t enjoy.” After a series of upgrades, National Express coaches are smart and comfortable, with reclining seats and air conditioning. And the firm is about to unveil some whizzy on-board wonders to help the time pass pleasantly even when the M40 traffic grinds to a halt.

“We want to get you there in the right frame of mind,” says Mr Parmar. “We can’t change the road network, but we can improve the experience.”

In an era when time seems more precious than ever, coach travel has a basic problem: unlike the railways and the skies, which are largely closed and protected, Britain’s roads are full of the unpredictable public and their unreliable vehicles. My coach was not even out of the station before we had to stop, because a confused car driver was trying to drive in through the coach exit.

When things go seriously awry, National Express behaves differently from train operators and airlines. There is no fixed Delay Repay or EU-stipulated compensation, but instead a promise: “We will always get you where you need to be.” Coaches are re-routed around motorway incidents, while customer service staff organise (and pay for) taxis or trains as necessary when connections are missed.

Shortly after Oxfordshire merged into Buckinghamshire, there was an interesting pause to change drivers at a place called High Wycombe Coachway. While that might sound glamorous, it turned out to be a bus shelter beside the biggest Waitrose you ever did see.

When a Virgin Train stops at Milton Keynes Central on the way from Birmingham to London, it slows from 125mph to zero, pauses for a minute or two and accelerates away. It doesn’t wander off the main route, along the edge of a housing estate, through two sets of traffic lights and into a supermarket car park. The exercise took seven minutes, which was exactly how late my coach was arriving in London.

Time, though, isn’t everything. On National Express you are guaranteed a seat, a clean and proper loo and a company-wide positive attitude to accessibility.

Vinay Parmar has an unenviable task. He is well aware that some people perceive National Express — formed as a nationalised enterprise 44 years ago from a collection of regional operators — as a “legacy” brand such as BHS or Woolworths.

Involvement with Glastonbury helps National Express get its modernised message across: the firm takes one in four festival-goers to and from the Somerset site.