| A Week at the Wheel | Stirling, Scotland | BMW 120d SE Convertible |

Inside & Out:

There's an essential rightness to the BMW 120d Convertible's looks. Where it's Coupé and hatchback sisters can appear a little awkward from some angles, the Convertible pleases the eye no matter where you gaze from. Chopping the roof off was made it easier for BMW thanks to the natural flow of the 1 Series' curves from headlights through the window line to the stubby boot. It's also helped by using a fabric hood rather than the more common folding metal coupé-cabriolet style roof of most of the BMW's rivals. This also keeps more space free for rear seats passengers and luggage room in the boot, though you can extend the cargo capacity when the roof is raised by folding up a flap to release some of the space where the hood would otherwise rest.

For the driver, there's ample comfort and the steering wheel adjusts for height and reach. Moving the seat could be easier as BMW persists with its manual levers that require the driver to shift his or her body weight rather than the lever working by a ratchet mechanism. The rest of the driver's environment is typical BMW too, with clear instruments and a clean-cut dash style, though this is not to all tastes. That said, we love it. Rear seat space is tight for adults, but okay for children or short hops across town four up. With the roof up, rear vision is restricted by the hood sides and small back window, though this is made of glass and heated to demist quickly.

Engine & Transmission:

BMW's 2.0-litre turbodiesel engine is so smooth, refined and rev-happy, many will be fooled into thinking there's a petrol motor under the bonnet. It suits the 1 Series Convertible to a tee as it has just enough power at 174bhp and 258lb.ft of shove to keep the car ahead of the pack without taxing the chassis so far that it shows up any flex caused by the lack of a fixed roof. BMW has also made its usual superb job of the gearbox, which slices and dices between the six ratios with measured precision. Some drivers may find reverse a little tricky to locate at first, but a few practice goes will soon make them an accomplished expert at pushing the lever hard over to the left to select reverse gear.

With decent, though not exhilarating, performance the 120d's engine and transmission earn their full five-star rating courtesy of BMW's EfficientDynamics. This package of small energy and fuel saving measures may not sound like much individually, but together they make the 120d a very frugal, efficient and clean car. Measures such as the Auto Start-Stop, which switches the engine off when it's stationary, and brake energy regeneration to charge the battery all help. Other useful gains come from low rolling resistance tyres and electric power steering that only gives assistance when the steering wheel is turned. The results are carbon dioxide emissions of 134g/km and 55.4mpg combined economy, which is impressive for a sporty small open top car and the fuel efficiency gives the 120d a superb range on a single tank of about 620 miles.

Ride & Handling:

Drive hard on a bumpy country road and you may notice that the 1 Series Convertible is not quite as pin sharp when turning into a corner as the Coupé version is. However, in most circumstances, the Convertible is huge fun to drive and copes very well with criss-cross routes scattered with the usual array of British potholes and ridges. The steering suffers no kickback and remains faithful and accurate regardless of speed, and the run-flat tyres have no apparent effect on the ride or stability. Even with the low rolling resistance tyres fitted as part of the EfficientDynamics package, the 120d Convertible grabs hold of corners and won't let go until its aiming down the next straight. With the roof lowered, the 1 Series drop-top keeps its front seats occupants free from wind blast, but those in the rear will feel the gust. Roof up and the 120d shows off its hushed engine. Road noise is also effectively quelled, but a downside of the fabric hood is some wind noise and the whoosh of passing traffic.

Equipment, Economy & Value for Money:

At £26,250, the 120d SE Convertible is not cheap for a small open top, but then you are getting one of the best driving and frugal drop tops in its class. There's also the small matter of driving a car with the BMW badge on its bonnet, which elevates this car above several of its wannabee rivals without any effort on the 1 Series' part. In SE trim, the 120d Convertible comes with climate control, an electrically operated hood, rear parking sensors, multi-function steering wheel, alloy wheels, electric windows all round and an CD stereo with MP3 connector. You'll probably want to fork out on leather seats, metallic paint and heated seats, which will allow you to drive sans roof in colder weather. BMW's EfficientDynamics package comes as standard.

Overall:

Without EfficientDynamics, BMW's 120d SE Convertible would be a desirable small car, marrying a super-smooth diesel engine with neat looks and open air fun. Throw in the superb economy, efficiency and cleanliness of the car with EfficientDynamics, which is standard and requires no special effort on the part of the driver, and the 120d drop-top is one of the best cars in its class. It might not have quite as much rear seat space or a folding metal roof like some rivals, but the BMW is great to drive, well equipped and easy to live with. Drop top fun never looked so sensible.