Introduced last year as a more dynamic alternative to the X3, the BMW X4 trades interior space for style and sportier suspension tuning. A turbocharged engine line-up delivers 241 or 300 horsepower and xDrive all-wheel drive is standard. However, a new X4 M40i version that will hit dealerships in February, part of the M Performance product range, gets a new-generation turbocharged six with 320 hp and even sportier chassis tuning.