BMW's Z3 convertible arrived with considerable fanfare in 1997. Helped along by James Bond and the simultaneous release of the film GoldenEye, the Z3 soared to the top of convertible sales charts in Australia.

Much of its early success was also due to aggressive pricing - the BMW came in well under its German rivals, the Mercedes SLK and Porsche's Boxster.

But the honeymoon was relatively brief. Come 1998 and the Z3 was achieving close to saturation and the press continued to be unmoved by the 103kW four-cylinder's uninspiring performance.

The 141kW 2.8-litre variant that followed later in 1997 helped the image but a big price premium of around $20,000 kept away entry level buyers.

Now the base model Z3 has moved upmarket. The price has jumped substantially above the four-cylinder - by more than $11,000 - but so has the driveability.

As well as the smoother, slightly stronger engine, the base Z3 picks up the wide track rear end of the 2.8-litre model plus a reworking of the guards and boot lid - and tail-lights - that give a much more substantial look to the back of the car.

Inside, Z3 watchers will find a subtly redesigned centre console with matt chrome used on the console itself and on gear lever and door trim strips.

Importantly, and indicating where some of the $11,000 went, the base Z3 now also gets an electrically-operated roof, side airbags, standard roll bars behind the seats, a touch more leather and a hi-fi sound system with CD player.

So how does all this add up for the prospective Z3 buyer?

The power only creeps up slightly over the four-cylinder - from 103kW to 110kW - while torque rises from 180Nm at 4300rpm to 190Nm at 4200rpm, so the bottom line in terms of acceleration is not all that different.

But the 2.0-litre six sings a beautiful song which is enough in itself to justify its existence.

Working the Z3 up and down through the five-speed gearbox is such an aural pleasure that the new sound system is usually left switched off.

Acceleration is enough to avoid embarrassment, improving by 0.4 of a second to 9.1 seconds from zero to 100km/h. And while the response at engine speeds below 4000rpm may be a little languid, at least the Z3 gathers pace smoothly with a very BMW growl, not a little unlike that sung by the 236kW M Coupe, snarling through the cabin.

The shift/clutch action is relatively driver friendly which only encourages the driver to use the gears even more, as just slicking it up and down through the gears in traffic is an aural delight.

The trouble is the chassis feels that it would prefer a bigger engine than 2.0-litres. It seems BMW should either go for broke and inject more kilowatts or back off in the suspension settings and accept the fact this is a boulevard cruiser more than a weekend sportster. On the other hand, there is nothing wrong with chassis abilities outstripping engine capabilities.

Although it uses more fuel than the four-cylinder, the 2.0-litre Z3 is reasonably frugal - and it needs to be because the fuel tank is pitifully small at just 51 litres. This limits cruising range to an inconvenient 300km or so.

For the money, the buyer gets most of what would be expected although the part electric only (for height/reach) seats were a surprise as was the lack of steering wheel adjustment. The boot is pretty small too with the (temporary) spare awkwardly located on a wind-down frame outside the vehicle.

Headroom is pretty tight but general cabin space is okay although there are not a lot of handy spaces - and what is there is generally too small to be really handy. The in-built roll bars are a big safety plus, as is the standard fitment of side airbags.

The electrically operated roof is also more handy than the four- cylinder's manually operated version but it can still get a bit fiddly at the unlatching/relatching stage where the locating points can be occasionally misaligned. Slightly inconvenient is the fact the first 20 centimetres of lowering the roof must be done manually before the electric motors kick in.

On the road, the Z3 rides very well with minimal scuttle shake unless the going gets really rough. Steering response is pretty sharp and the wheel well weighted, although there is noticeable bump-steer on rougher surfaces which is a reasonable trade-off for the excellent grip.

The Z3 also gets traction control but the grip of the tyres plus the shortage of low rpm torque means it rarely gets to kick in, even if the road is wet.

In all, the 2.0-litre Z3 makes the jump from questionable to credible in the two-seat sports convertible market. It is pure pleasure to drive - helped along considerably by the magic of the six-cylinder engine note - and the roadholding abilities of the suspension are comfortably beyond what the engine dishes out.

It also looks more balanced, more muscular from every angle and is comfortable and accommodating inside. Down points? It costs an awful lot more than the original Z3.