Living on an almost exclusive diet of week long loaner vehicles definitely spoils a journalist. Dirty? Get a new one. Tank empty? It's being collected tomorrow. Running a long term car requires a slight shift in focus. Territory alien to many motoring writers - the petrol station for instance with its curious fuel pumps and car washing apparatus - suddenly start to figure in one's motoring week. We took on a Citroen C4 1.6 HDi diesel fitted with the ingenious Electronic Gearbox System to see how it would fare at the hands of some very demanding users.

Some of them noted a degree of complexity about the car that took them a weekend to get to grips with and it's true that the advertising strapline 'Alive With Technology' does apply in this instance. There's a lot to figure out, even in our car which wasn't equipped with satellite navigation, the most notable feature of this model being the Formula 1-style sequential manual gearbox. If asked what part of the C4 was most likely to go wrong prior to delivery, I'd have certainly plumped for this EGS transmission but it hasn't missed a beat and has proved hugely popular with all testers.

Up to now, there have only been a vanishingly small number of truly satisfactory sequential manual gearboxes. At the top of the tree is VW's DSG system, now confusingly dubbed S-tronic by Audi. Beyond that, there have been some really poor systems such as Ferrari's initial incarnation of the F! system and BMW's first SMG gearbox but since then things have been improving. In the realms of 'real' money, this Citroen EGS system is the best you can buy, producing snappy shifts, imitating heel and toe downchanges and achieving 0-60mph sprint times that would be beyond even the most skilled drivers in a manual car. Such systems now routinely achieve lower fuel consumption than equivalent manual models and the they're even starting to get reasonably accomplished at aping the velvety shifts of a genuine automatic when left to their own devices.

Citroen confidently wheels out the oft repeated claim that their set-up combines 'the convenience of an automatic with the driver involvement of a manual' and, to be fair, it has a good go. There's no clutch pedal or manual shift lever, at least not in the traditional sense. The cogs are swapped electronically by a computer and a robotised clutch but some element of driver control is maintained through the steering wheel mounted paddle shifters and a gearstick that, when flicked back and forth, also lets you hop up and down sequentially between the ratios. There will be many times when you just can't be bothered with all this though and the EGS has a fully automatic mode.

"The EGS gearbox makes this C4 feel something distinctly out of the ordinary"

When you do feel like pressing on, the 'S' button next to the gearlever puts the EGS into sport mode, a setting where the gearchanges are quickened up by a few important fractions of a second to create a livelier feel behind the wheel. Another clever component of the system is the hill-start assist function that prevents the car from rolling away when you're trying to pull away up or down a gradient - a common problem with self-shifters of old. The system engages automatically when a gradient of 3% or more is detected; it then acts to hold the car stationary for two seconds after the brake is released giving the driver time to get on the throttle.

The EGS is, in this case, paired with the popular 110bhp 1.6-litre HDi common-rail diesel engine. It's a powerplant that's biased more towards economy than performance. Citroen claims that the EGS achieves fuel savings of 6% over a manual C4 with the same engine: this translates into an excellent combined fuel economy figure of 63mpg although our lead booted testers averaged in the low fifties. The presence of Citroen's Diesel Particulate Filter System (DPFS) helps to make this an extremely clean car in terms of soot in the exhaust gases and CO2 emissions of 120g/km make sure that the taxation burden is agreeably light as well. The economical nature of the C4 1.6 HDI EGS along with its clever features and performance figures that are identical to the manual car (0-60mph in 11s and a 119mph top speed) mean that buyers should be content to pay a premium to get their hands on it.

Solid and safe, a little complex maybe, but far from the usual family fare, the C4 feels as if it's now getting into its stride in our hands. We look forward to the next few months with interest..