WHEN MERCEDES rolls out a new SLK, the world takes notice, for no grand-touring roadster quite has the pedigree or cachet as the baby Benz retractable hardtop convertible – or at least, that’s what the company says.

But the R172 is indeed (mostly) all-new, with worthwhile safety, driveability and convenience gains, topped by refreshed and revived styling that connects the series with both the animalistic SLS Gullwing and the 1950s 190SL.

Should the Porsche Boxster and BMW Z4 be worried?