With its new roof and great looks, the 3-Series Convertible is the pick of the class - BMW has done a fine job of engineering a folding hard-top that doesn't compromise the shape and style of the body. Boot space has suffered, but excellent strengthening means the Convertible shares the impressive handling of the standard Coupé. Add in excellent refinement both roof up and down, and the 3-Series makes a fine choice.

In light of the UK's recent freezing weather, it's hard to believe spring has finally arrived! However, blossom on the trees and a host of new convertibles hitting our showrooms are a sure sign summer is on the way.

One of the most important arrivals is the new 3-Series Convertible. Having reached its fourth generation, its blend of style and driver appeal has always made it a class benchmark. And now the Bavarian firm has given its open-air four-seater a folding hard-top - a first for BMW.

Designers have done a great job meeting the challenge of the new lid - for starters, roof-up refinement is excellent, while the entire canopy folds in only 22 seconds. And using a three-part mechanism, it can be stored without needing a bulbous rear end to accommodate it.

This means the Convertible retains the traditional long, horizontal wedge shape of previous open-top 3-Series, and looks very similar to the Coupé with the lid up. It also benefits from smaller C-pillars and a far bigger glass area than would be afforded by a fabric hood. The only downside is that the boot is 50 litres smaller roof down than before. However, BMW has at least included an easy load facility, which lifts the hood panels high enough to access the boot without the need to completely close it.

As with the outgoing car, the 3-Series will carry four in genuine comfort, while wind buffeting is well suppressed at speed. The dash is as in the Coupé, while the driving position is similarly excellent. What's more, the level of chassis stiffening means it delivers the same driving experience as the fixed roof model. With the hood stowed, there's a lack of body twist, and the Convertible retains the same involving dynamics of its brother.

With peak torque delivered in a flat curve from 1,300 to 5,000rpm, the 335i has fantastic flexibility, and the open-topped car allows for more appreciation of the exhaust note. Add in usual 3-Series traits of sharp steering and strong brakes, and the new Convertible is as good to drive enthusiastically as it is to cruise in.

Even the ride isn't particularly hard - there is some firmness from the low-profile run-flat tyres, but it's well damped and, unlike some cabriolets, suspension control hasn't suffered at all as a result of losing the roof. So with the 335i and 325i petrol models on sale now, and the 320i, 330i and 330d all set to arrive in April, the 3-Series Convertible is sure to make this spring a happy one for lucky owners.