14. Mazda6 MPS / Mazdaspeed6
The Mazda6 MPS (or Mazdaspeed6 in the US) hides its turbocharged engine and all-wheel drive behind understated styling. This unassuming sedan delivers punchy acceleration and exceptional grip, making it a real threat to muscle cars at any stoplight.
As CarBuzz notes, the Mazdaspeed6’s performance credentials and stealthy looks have earned it a dedicated following among fans of secret speed.