It doesn't seem like six years since the Boxster first appeared, a testament to the enduring freshness of its design and the depth of its dynamic ability. Bolstered in 1999 with the introduction of the more powerful Boxster S, Porsche's entry-level sports car continues to exceed sales expectations, accounting for more than ten per cent of global roadster sales. This, together with the continued popularity of the evergreen 911 range, has enabled Porsche to become one of the most profitable car makers in the world less than a decade after teetering on the edge of financial oblivion.

From an outsider's perspective, meddling with the Boxster's winning formula might seem unnecessary, risky even, and Porsche itself admits it had to 'tread very carefully' with the revisions. That's a coded acknowledgement that the '02 Boxster is very much a product of evolution rather than revolution.

Sure enough, the 'new' Boxster is very, very similar to the original. Those familiar 'fried egg' headlights sit atop a mildly tweaked nose that features - wait for it - redesigned air intakes! Yes indeed ladies and gentlemen. Re-contoured to deliver a greater engine cooling ram-effect, the new intakes are deeper and now feature a pair of horizontal slats whilst, as before, a third, central intake distinguishes the Boxster S from the Boxster.

The ducts mounted in the car's flanks are now body colour and also feature horizontal slats, while at the rear the bumper is deeper, with two narrow vent slits emphasising the centrally mounted exhaust. Apart from the badge and front intake, the tailpipes (large, single, oval for the Boxster: a pair of large round pipes for Boxster S) are the only other visible difference between the two models.

Both our test Boxster and Boxster S came fitted with new 911-style 18in alloys, which is a shame as we didn't have the chance to try a Boxster on standard 16-inchers, or an S on default 17-inch wheels. However, the optional rims are over 3kg a corner lighter when compared with the previous wheels, which is a significant reduction in unsprung weight. They also look fantastic, complementing the Boxster's sharp lines to perfection. Whether 911 owners will agree is debatable, because they make the Boxster look more than ever like its pricier sibling.
Thanks to the adoption of Porsche's VarioCam technology, both the Boxster's 2.7-litre flat-six and the Boxster S's
3.2-litre version are more muscular, developing 228 and 260bhp respectively. That's an increase of 11bhp for the Boxster and 8bhp for the S. Rather oddly, the revised 2.7-litre engine doesn't develop any more torque than the old motor, while the 3.2 gains 3lb ft. The net result is a fractional reduction in 0-62mph times, the factory claiming 6.4sec for the Boxster, 5.7sec for the S.

We've always erred towards the base Boxster as an all-round package, simply because ΂£7000 seemed an awful lot to pay for the S's extra performance. With this in mind we grabbed a 2.7 Boxster first and headed into the hills south-east of Rome to get a benchmark with which to compare the S.

True to form, the 2.7-litre engine needs working pretty hard to get the Boxster moving with conviction. The hilly roads and tight corners don't flatter it, especially when lugging out of second-gear uphill turns. At nearly 1300kg the Boxster is no lightweight, and with a modest torque peak of 192lb ft arriving at 4700rpm you can find yourself becalmed in the thin end of the Boxster's torque curve. However, once you get enough revs dialled in to reach the point where maximum torque melds with burgeoning bhp the Boxster feels more convincing, but keeping it in the 5000rpm sweet-spot is hard work on such steeply contoured roads.

Attack the same roads in the Boxster S and you're instantly aware of its added muscularity. It lugs where the Boxster flounders, that extra half litre, 32bhp and 36lb ft of torque making lighter work of gradients that have its little brother puffing and panting. Overtaking is easier and more decisive as a result, and the S is better equipped to get the chassis working, especially when shod with the optional 225/40 front and 265/35 rear tyres. As you'd expect, the 2.7-litre car is massively over-tyred on these rims - 228bhp is never going to worry such monster rear tyres - but it sacrifices little in wheel control, ride quality or, surprisingly, steering feel.

Both the Boxster and Boxster S have exemplary chassis. You feel completely involved in the car, aware of the slightest shift in balance, the merest whiff of turn-in understeer or lift-off oversteer. Perhaps more miraculous is the Boxster's ability to exploit the theoretical advantage of the mid-engined layout (50:50 weight distribution) without succumbing to intimidating on-limit behaviour. You really can push very, very hard in either car and never feel like you're trying your luck. The boundaries are so clearly defined and so accurately and progressively telegraphed that you always keep pace with the car's responses. In many ways it's like a 911 without the edge: this is a car that takes little learning but still feels hugely rewarding to drive.

Of course the same criticisms hold true with the revised car. If you're after raw pace then Honda's S2000 comprehensively outperforms the Boxster for much less money, while TVR's Tamora takes the fight to the Boxster S for a similar stack of cash. Many people have made those points, and they're valid ones, but it's the satisfaction you get from the overall Boxster package that makes it such a compelling car. There simply isn't a better all-rounder in the sports car sector because nothing has a better chassis, superior build quality or a stronger image than the bottom rung of Porsche's ladder.

True, it could be gruntier, especially the basic car (which may explain why 45 per cent of buyers plump for the S), but both engines are still absolute gems. Smooth and refined from idle to 7000rpm, both emit a hair-prickling howl as you work towards the red line, and unless you're chasing a faster car or attacking a series of mountain hairpins, in truth even the vanilla Boxster feels brisk enough to bring a smile to your face. Once you've tried the S, however, you can't help falling for the extra shove in the back - although stomaching the extra cost is another matter.

These Boxster revisions don't move things on significantly but they add lustre to an already polished package. What's more, Porsche's rude financial health has enabled it to peg prices at the same as the outgoing models', which is to say around ΂£31,500 for the Boxster and ΂£38,000 for the S. Though undeniably conservative, this revamp is if nothing else a timely reminder of just how good Porsche's baby is. It'll take a serious shake-up of the sub-΂£40K sports car sector to threaten Porsche's pre-eminence. Business as usual then.