However, the late 2000s international regulations trends on reducing CO2 emissions and fuel consumption are cited as the reasons not to continue further development on naturally aspirated high redline engines. The N54 twin-turbo inline-6 which debuted in the 2007 BMW 335i (E90) gives almost equivalent performance to the E46 and E90 iterations of the BMW M3, while being much more practical and fuel-efficient as a daily driver. Starting with the X5 M and X6 M, and featured in the F10 M5, BMW used the twin-turbocharged S63 which not only produces more horsepower and torque, but is also more efficient than the S85 V10. Also unlike the S85 and S65 which do not share a design with non-M BMW engines, the S63 has significant parts commonality with the base N63 V8 engine (which is also has twin turbochargers) making them less expensive to build. BMW has not yet considered supercharging.