Here's a comparison test that we're a lot of you were expecting: the 2015 Subaru WRX STI against the Audi S3 Sedan. Subaru's 2015 WRX STI comes with a 2.5-liter turbo engine that develops 305 hp and 290 lb.-ft. of torque. Audi's S3 Sedan comes with a 2.0-liter turbocharged engine that's good for 300 hp and 380 Nm of torque. Both have a very capable all-wheel-drive system.