Like Infiniti's G25 Sedan is to the G37, the Lexus IS 250 is essentially a doppelganger to the IS 350, with the main difference being that of power. And it's a big difference.
The reason for the power difference is the engine: instead of the IS 350's 306-horsepower 3.5-liter V-6, the IS 250 uses a 2.5-liter V-6 rated at 204 horsepower. Paired with the six-speed manual transmission, it's a fair, if not peppy, powertrain. With the automatic gearbox, however, it's a bit sluggish.
Unlike the Infiniti, however, the IS sedan line doesn't appeal to the enthusiast market, as its driving dynamics are decidedly on the comfortable end of the spectrum. It does comfort quite well, though, and the cabin is very well-appointed.
In design terms, the inside is growing a bit dated, with some textures and materials you won't find in most of today's luxury sedans. Cabin noise can be a problem, too, especially when compared to more recently redesigned competitors like the BMW 3-Series and the...