There's a wide choice of engines and all provide plenty of power and pace – from the four-cylinder 320i to the V8-powered M3, which goes like a rocket. Elsewhere in the petrol range are the 325i (our favourite) and the six-cylinder 330i and 335i engines. The four-cylinder 320d diesel engine is a peach, while the six-cylinder diesels (325d and 330d) are even sweeter.
The Convertible’s suspension is a little softer than the Coupe's, and the whole car is a lot heavier. This does change the ride-and-handling balance, and it’s not quite as sharp. It still handles better than most rivals drop-tops, though, and maintains most of the responsiveness and feel expected of a 3 Series. The ride is rather firm, though.
Put the roof up, and you can see why BMW wanted a metal-roof coupe-cabriolet rather than a soft-top: the 3 Series convertible is as hushed and weatherproof as a saloon. Even with the car fully open (roof and windows down), it's acceptably draught- and din-free for anyone in the front seats, and road- and engine noise never become intrusive.
Prices aren't cheap and you won't get much of a discount, even if you buy online. However, strong residuals mean you'll get plenty back when you sell. Running costs are competitive, too. The engines are frugal despite their power, and low emissions keep company car tax bills down.
Mechanically, BMWs rarely give trouble, so there's no need to fear problems. Owners rated the mechanical reliability of the 3 Series as average in the 2012 JD Power survey. Build quality - both the choice of materials and the way they are put together - is exemplary.
A coupe-cabriolet is always going to provide a sterner test for thieves than a soft-top - one of the reasons why they are now so popular. Safety provisions are all you'd expect from BMW, with stability control, self-drying anti-lock brakes, two front airbags, big body-and-head side airbags and automatically activated rollover hoops fitted.
The folding metal roof does wonders for visibility in the 3 Series convertible. Compared with a traditional cloth roof you can see more of what's behind. It's hard to fault the adjustability of the driving position or the control layout, too, which will include BMW's brilliant iDrive if you choose the sat-nav option.
No convertible is the last word in practicality, but the 3 Series doesn’t do too badly. Yes, rear head and legroom are a little limited, but there’s still enough room for four adults to travel in relative comfort. The boot is decent, if not huge, and the rear-seat backrests fold down to provide useful extra storage space. There's a through-hatch for skis and golf bags, too.
Every model has a healthy standard specification, including niceties such as automatic lights and wipers, electric seat adjustment, rear parking sensors and automatic air conditioning. However, there's plenty more you can add, such as leather trim that reflects much of the sun's heat.