Excellent though the 5 Series is, you do not stay at the top of the executive saloon pile by resting on your laurels – which is why BMW has refreshed it.

To test the raft of changes on offer, I drove the 520d in M Sport specification

– and I’m delighted I did. To start with, the M Sport pack adds a bit more bite to one of the 5 series’ biggest criticisms, its styling. It can often look too bland and a bit dull, though considering BMW took a lot of stick for the previous 5 Series being overly designed, I guess the Bavarian firm just can’t get things right. And if the biggest criticism for a luxury car is that it looks very restrained, then you aren’t doing too badly at all. The refresh has addressed some of these points though and it looks better as a result with new headlights, a changed grille and altered lower air intake. There are a few extra creases around the bodywork and the rear lights have been altered too but it is definitely an evolution rather than a revolution. You have to look carefully to really see any difference in exterior design.

The inside remains largely the same and is still a lovely place to sit in, looking stylish and feeling bombproof. There have been upgrades to the technology behind the scenes though with BMW’s ConnectedDrive having been expanded to make the ‘Business’ navigation system standard on all specifications and the ‘Professional’ set-up on every six-cylinder model.

The biggest changes, in true BMW tradition, have come in terms of driving dynamics.

The engine I tested for example is a significant shift for BMW as it has caused the EfficientDynamics model – the most eco-friendly version – to disappear from the 5 Series list. The latest 2.0 litre diesel unit achieves all the original EfficientDynamics parameters by offering 62.8mpg and emissions of just 119g/km CO2. These are fantastic results from a big executive saloon, especially considering the 520d still puts out 184hp and 280 lb ft of torque. These strong figures will get the 5 Series from 0-62mph in 8.1 seconds for the six manual and slightly less with the eight-speed auto’box.

Obviously all the power gets put through the rear wheels and helps make the driving experience as good as a 5 Series should be.

The handling is superb with quick steering and a precise action that encourages you to make the most out of the well sorted chassis. Make sure you opt for the variable damping option and the BWM will handle like a sports car round the bends, staying flat and accurate. When you get onto the motorway though, it will soften and allow you to cross countries in comfort.

It is always difficult to make a class-leading vehicle better but BMW has taken the right approach, focusing on small details and improving them. The interior has hardly been touched but, considering it is extremely comfortable to start with and has a high level of fit, finish and space, there was little point in changing that much. The only downside is that the transmission tunnel eats into the central seat of the rear bench’s footspace – but BMW can do little with that while keeing the 5 Series rear-wheel drive.

The engines, already a strong aspect, have been improved further and the technology on offer has been made available to a greater proportion of buyers.

With the 520d M Sport, I think BMW has produced one of the best cars money can buy – especially if it’s your own money you’re spending. It is cheap to run, has the right level of performance to keep you powering forward but without the excess power that makes it expensive in running costs. It handles engagingly, cruises beautifully and overall, hits the right balance needed for a car to be used every day.

The styling is now better than it was, though the Audi A6, Mercedes E-Class and Jaguar XF all look more stylish. I think one of the main problems with the design is its familiarity. We see so many BMW 5 Series’ on the road and there’s a very good reason for that – it’s simply the best in its class.

Drive Specs – BMW 520d M Sport Saloon

OTR Price on the road: £34,330
Engine: 2.0 litre, 4 cylinder diesel
Max power: 181 bhp
Torque: 380Nm from 1750 rpm
0-62 mph: 8.1 seconds
Top speed: 141 mph
Claimed combined mpg: 57.6
Emissions: 129 g/km Co2
Insurance Group: 11E