Overall: BMW makes the 4 Series in a drop-top convertible, four-door Gran Coupe and the big-power M4 better looking with subtle updates.
Drivetrain: The 428i uses a 240-horsepower turbocharged four-cylinder engine; 435i puts you in control of a 300-horsepower turbocharged inline-six, which is boosted to 425 horses in the M4; six-speed manual or eight-speed-automatic-transmission option.
BMW is now several years into making its even-numbered models the more exciting, stylish and desirable ones in the fleet. Buyers seem behind it too, which means the 4 Series line, which cuts a wide swath, remains a gold mine. All variants use the 4 Series coupe as a basis, although the Cabriolet obviously ditches the fixed roof in favor of a complex folding metal hardtop. The roof can be raised or lowered in about 20 seconds, although you must be nearly stopped before it operates. At the other end of the spectrum, the 4 Series Gran Coupe four-door model mimics its larger 6 Series sibling, meaning an even lower roof and much longer body, which — somewhat bizarrely — uses a hatchback to access the cargo area, like the Audi A7. The high-performance M4 and M4 Cabriolet get more aggressive body bits that are expected of the M cars, including a carbon-fiber roof for the coupe and huge fenders covering wide 19-inch-diameter wheels and performance tires. The front and rear get similarly striking bits that are all designed to send as much air through the engine bay as possible for cooling and intake. The M4 uses a 3.0-liter inline straight-six engine and with two turbochargers that produces 425 horsepower and 406 pound-feet of torque. It uses either a six-speed manual transmission or optional seven-speed paddle-shift manual to send power to the rear wheels. The base 428i models come equipped with a 240-horsepower 2.0-liter turbocharged four-cylinder and the 435i uses a 300-horsepower six-cylinder engine, which makes for a 60-mph-sprint time of 5.3 seconds. Either engine is connected to a six-speed manual transmission, or optional eight-speed automatic. You can also equip most 4-series cars with x-Drive all-wheel-drive, although they use the Sport line as standard trim. That means 18-inch wheels, high-gloss black bits around the air intakes and grille, and rear bumper, a back-chrome exhaust tip, and sport-style seats. Those missing the Luxury line can add most back through a no-cost option.