MMC stage 1 kit was everything I needed for massive fun.
Little bit noisy but soooo much better. I don‘t remember if the air filter was part of the upgrade or if I did it seperate but that had been changed too
The MMC Stage 1 is exhaust pipes and air filter. Definetly a worthwhile upgrade, the engine breathes so much better, and runs cooler.
One thing to bear in mind is the exhausts are designed for 2014 cars onwards, so if you want to continue to use heat shields you will need new exhaust mounting brackets and new heat shields, as the heat shields are mounted from the brackets rather than mounted on the silencers.
When I did mine the MMC price with new heat shields and brackets was comparable to G56
