It’s hard to list the IS as anything other than an also-ran in this department. Lexus's asking price of under around £29,000 for the desirable F Sport trim is barely changed from the price of the equivalent IS220d that came before it as part of a series of mid-life revisions. That makes it more expensive than the new BMW 320d Sport.
In every other respect, the BMW (181bhp, 280lb ft, 61.4mpg and 120g/km) also trounces the Lexus. As does the Mercedes-Benz C220 CDI Sport, even though it is more expensive still. Going in the opposite direction on price, the BMW 318d Sport, although less powerful than the IS200d, is still faster and more economical.
The IS can be had from around £25,000 in its cheapest SE guise. All IS diesels sit in insurance group 25, whilst the petrol IS250 sits in insurance group 29, and offers 33.6mpg economy and 194g/km CO2 emissions.
A £9000 premium over the saloon may look rich for a folding metal roof, but it places the IS250C broadly in line with the equivalent BMW or Mercedes. Ignore the top-spec models and look instead at the still-well-equipped SE-I model at under £37,000.