Let's face it, the BMW 3-series is no longer the sporty compact it once was. It has grown too big and its smaller sibling, the 1-series, has overtaken it as the essential sports compact for the young at heart.

But when compared with the Mercedes-Benz C-class - long considered to be the 3er's arch rival - the Bavarian still has an edge.

This is because the C-class has grown even more, coming across in many ways as a miniature of the S-class limousine. With its unusually big body and long wheelbase, it has all but lost the dynamism found in its predecessor - a car that came closest to matching the 3-series in the fun-to-drive department.

While the 3-series still handles better than the C-class, BMW does itself no favours by pitting the 318i against the C180 as an entry-level model.

The facelifted 318i is powered by a 1.5-litre three-cylinder engine that makes 136bhp. Which means it has noticeably less oomph than the C180's 156bhp 1.6-litre four-cylinder. At the same time, it fails to make it into the Category A COE by just 6bhp and hence has no significant value advantage over the C180.

To rub salt in the wound, the 318i's fuel economy and carbon emission figures are only slightly better than the C180's.

But against its own pre-facelift 316i, a 1.6-litre four-pot, the latest entry-level 3-series makes sense. It matches the 1.6-litre's output, is a mite quicker because it is lighter and is more efficient because of its cylinder and capacity deficit.

At the wheel, the 318i's threecylinder engine is not as smooth nor rich-sounding as BMW's four-cylinder power plant (probably the best four-cylinder in the world), but it does a decent job all the same.

With low-friction cylinder walls and balancer shafts, the diminutive engine is smoother than others of the same configuration.

But this engine fails to deliver the sportiness you have come to expect of BMWs. Perhaps it has to do with the sheer size of the 3er sedan as well as the fact that the frontmounted engine has to power the rear axle situated nearly 3m away.

Often, you find yourself squeezing the throttle hard to get the car going. To its credit, the tiny engine puts up a brave performance when pushed. And it does not complain even when you rev it to 6,000rpm.

At the lights, it beats the 1.6-litre Japanese sedans (but not the C180) to the next junction. Because you are at the wheel of a BMW 3-series, you drive it with verve every chance you get. And because it is this particular 3-series, your right foot is also heavier than usual.

The consequence to fuel economy is obvious. In the real world, the test car turns out to be thirstier than its 1.6-litre four-cylinder predecessor tested two years ago.

If, however, you drive it with less urgency, the car surprises you with a measure of effortlessness. For instance, it rolls on for quite a distance when your foot is off the throttle, matching the coasting function found in Audis.

Like the pre-facelift 3er, it offers a decent ride and lots of cabin space (although not as much as the C180). It also acquits itself fairly well around corners, but you might occasionally have to shift down manually to set the car up for a swift exit out of a bend.

All in all, you will do better looking at the C-class if you want comfort and refinement, and the 1-series if you want fun and games. The 3-series, in this form, is just too much of a compromise.