What is it?
The roadster variant of the Exige is ostensibly the same as the Exige S coupé, most notably with the roof removed and replaced with a hood from an Elise (the Exige and Elise share the same chassis tub).
But the Exige Roadster is different, not just to the Elise (it has a 70mm longer wheelbase, is 243mm longer overall and has a supercharged 3.5-litre V6), but also, subtly, to an Exige coupé, too.
Changes are small but significant. Gone is some of the coupé’s aero package, specifically the front splitter and rear spoiler. That lowers drag minutely (by about Cd0.04) and makes a larger difference to downforce. Not enough that would trouble most manufacturers, but, well, this is Lotus.
So the rear roll bar has been stiffened to keep the back feeling planted at speed, while geometry changes at the front (where negative camber is reduced) and the rear (where negative camber has increased) attempt to compensate similarly. The front changes also reduce steering effort at manoeuvring speed, helpfully.