Tale of the tape: Cadillac CTS Vsport vs. BMW 550i vs. Mercedes E550 4MATIC

Nothing exemplifies the arms race among German luxury automakers quite like the technology they've poured into their mid-size sedans, turning them into 400-hp dens with Internet access. Those models aren't their best-sellers, but they're the epitome of what a luxury car should be. With the 2014 Cadillac CTS, General Motors aims to close the perception gap between its U.S.-built challenger and the establishment — and on paper at least, that matchup looks too close to call.

For this tale of the tape, we've compared the top-end sport versions of the midsize luxury models — the new Cadillac CTS Vsport that will go on sale this fall, the BMW 550i and the Mercedes-Benz E550 4Matic. The similarities spring forth instantly; all have more than 400 hp, use automatic transmissions of at least 7 gears and come within a fraction of a inch in many dimensions. The differences come down to some hard engineering choices: Cadillac chose a twin-turbo V-6 to replace the displacement that BMW and Mercedes rely on, winning the horsepower war while ceding the torque figures to the Germans. Yet the Caddy claims to be a few tenths of a second faster to 60 mph, largely due to the lightweight chassis that 200 lbs. lighter in base form than the BMW. (Mercedes alone offers a hybrid model in this class.)