Convertibles trade structural rigidity and boot space for open-air driving, and the segment is shrinking – cabriolet listings have fallen by roughly a quarter across western Europe since 2021. It remains a niche for enthusiasts, split between affordable roadsters like the Mazda MX-5 and premium offerings from Porsche, Mercedes-AMG and BMW. From our coverage, the BMW Z4 shows how a modern roadster balances summer-weekend character with day-to-day usability.