Powerful, smooth and refined even with the top off
Perfect driving position, great visibility and pure luxury
Open-top motoring doesn't come much more secure
Should be unbreakable, but the new roof is yet to be proven
The roof mechanism means that boot space and rear seating is compromised
We're not sure what else you'll need in a car
The suspension is slightly softer than the coupe's, but there's still an edge to the low-speed ride (particularly on M Sport models) and the 3 Series Convertible offers outstanding agility and composure in bends.
With its folding metal roof in place, the car is as quiet and weatherproof as the coupe. In fact, even with the roof open and the windows down, it's acceptably draught- and din-free for anyone in the front seats.
Our favourite model is the 325i, because it combines lively performance with a musical exhaust note and sensible running costs.
Alternatively, if you're on a more modest budget, the 320d diesel's flexible performance and impressive efficiency make it worth a look.
Even with the roof up, all-round visibility is surprisingly good much better than in cloth-roofed rivals - while the dashboard is classy and simple, and the driving position close to perfect.
Rear space is less impressive, even if adults can fit for short journeys, and the boot is less than half the size of the coupe's when the roof is folded away.
More positively, the rear backrest folds down to provide useful extra storage space, and there's even a through-hatch for skis and golf bags.
Every model comes with alloy wheels, cruise control, leather upholstery, rear parking sensors, climate control and a CD player with an MP3 input.
Owners of the previous 3 Series saloon, which this car is closely related to, rated it just average for mechanical reliability in the most recent JD Power customer satisfaction survey.
Fortunately, that model did better in Euro NCAP crash tests, scoring five out of five for adult occupant protection and four out of five for child safety.
The 3 Series Convertible comes with a long list of standard safety features, including stability control, electronic brakeforce distribution and front and rear ISOFIX child seat mountings.
The 3 Series Convertible is one of the best four-seater convertibles on sale, although it's due to be replaced soon and we'd recommend you also try the Mercedes E-Class Cabriolet before you buy.