Far from being a means of taking a few people from A to B cheaply, as was originally intended, customers now expect much more.
For years, manufacturers have claimed that these vehicles include big-car features, but it is only now that we can appreciate the sheer scale of these 'small' cars - it is the motoring equivalent of middle-aged spread.
The previous Polo was apparently as big as the original Golf, while the new model is thought to be somewhere between a Mark 2 and Mark 3 Golf. In fact the previous Polo had grown so big that VW had to invent the Lupo to become the entry-model.
The trend has spread, too. Peugeot came up with the 106 to keep pace with the supermini growth spurts, the Vauxhall Agila was shuffled in below the Corsa, and the Ford Ka made the Fiesta look a little chubby.
The latest Polo arrives amid a flurry of activity in the small car sector, launched at the same time as the new Honda Jazz, and ahead of the latest Ford Fiesta and new Citroen C3.
The range begins with a 65bhp three-cylinder 1.2-litre engine and we have tested the three-door SE version, priced at £10,995. For £10,295 on-the-road you could choose a Renault Clio 1.4 16v Privilege, while for the same price a Vauxhall Corsa 1.2 16v Elegance also looks attractive.
Despite being the most expensive to buy (jointly with the Corsa we have chosen) the Polo seems untouchable in terms of its residual values.
Polos have long been the depreciation benchmark in the sector, and with a predicted residual value of 43% after three-years/60,000-miles it performs significantly better than its two rivals.
It means the Polo would lose about £6,200 during this period, compared with £6,570 for the Clio and nearly £7,300 for the Corsa. It equates to a depreciation cost of 9.67 pence per mile, compared with 9.77 for the Clio and 10.62 for the Corsa. The Vauxhall and Renault claw back some of their lost ground in SMR costs, priced at 1.95 pence per mile each compared with 2.12ppm for the Volkswagen. The frugal Polo goes on the offensive again in fuel costs with an impressive 47.1mpg, translating to 8.10ppm. The Clio manages 42.2mpg or 9.04ppm while the Corsa is a little better on 44.8mpg or 8.52 ppm.
Although the Corsa is more powerful than the Polo (74bhp compared with 65bhp) both have comparable levels of torque. However, the Clio's 1.4-litre engine develops 95bhp which goes some way to explaining its fuel consumption disadvantage, and with a list price that significantly undercuts the other two, it must be kept in contention.
The Polo's low carbon dioxide emissions of 144g/km mean it will be taxed at 15% for the first three years of the new benefit-in-kind system.
The Clio would have a small advantage in the first year of the new rules, while the minimum threshold is set at 165g/km, but at 160g/km it would creep into the 16% band in year two and then 18% in year three.
The Corsa, although more expensive from a BIK perspective in the first two years through its higher P11D price, will nip ahead of the Clio in year three thanks to its lower emissions.
THE Polo is fun to drive and has impressive build quality, and its high RVs ensure it remains an inexpensive whole-life cost proposition. However, when you look elsewhere you can find more powerful and better equipped rivals for a small difference.
Although we would strongly recommend it, the Clio 1.4 Privilege seems excellent value alongside it with a significantly more powerful engine and higher specification. Much as we like the Polo, and we know the Clio does not feel as well screwed together inside, this kind of disparity is enough to tempt us to choose the Renault.
Behind the wheel
THE new Polo shares a strong family resemblance with the smaller Volkswagen Lupo, and there is a hint of Passat around the rear light clusters.
But despite sharing the same cute face as the Lupo, the Polo seems more mature. Inside, the Polo will be familiar to anyone who has seen the inside of a Volkswagen. The four-spoke steering wheel comes from the Lupo, while the blue-backlit instruments are a reassuring touch.
The most noticeable evidence of the Polo's increase in size is the width across the passenger compartment. It really makes the Polo seem like a bigger car. The plastics are of the highest quality and the fit and finish is millimetre-perfect.
Keen-eyed drivers will also spot the new type of plastic windscreen wipers, which supposedly reduce noise and are more efficient, and were first seen last summer on the facelifted Audi A6. The 1.2-litre engine starts with a typical three-cylinder rasp, but its off-beat sound is subdued while on the move.
Although it is lacking in power when compared with similarly priced rivals, there seems to be ample torque to keep the car chugging along.
However, the Clio's formidable 1.2-litre 95bhp engine would make the Polo seem a little asthmatic. The Clio has a feisty exhaust note and the engine willingly tears off towards the red line, sounding refined and almost unbreakable at high revs.
The Polo's electronic power steering is sharp and communicative, making stringing a series of corners together an appetising prospect, while the suspension keeps body roll in check. Ride quality, helped by the car's broad-shouldered stance and long wheelbase, is also stable and smooth.
THE Polo is the sensible choice, but it manages to combine being sensible along with being fun and the engine is a gem. Its frugal nature means you can allow the rev-counter needle to get lively without a significant penalty at the pumps and it makes a refined cruiser. It is also roomy and build quality is as superb as you would expect from Volkswagen. Not only does the new Polo set the class benchmark for quality, it is also an entertaining car to drive, giving it the broadest appeal of any car in the sector.