The X4 is a coupe-like variant of the X3 crossover. While it boasts a sportier appearance, rear visibility and rear-seat headroom are limited. Unlike the X3, the X4 doesn’t offer a plug-in hybrid variant. The iDrive infotainment system is attractive and user-friendly, material selection is commendable, and the top-line M Competition model (503 horsepower) delivers all the thrills you want. Beware of the stiff suspension, though.