Just want to give people a heads up this achievement is a little buggy but still achievable, i completed both insane hills & stadium stunts all with 10 stars and the achievement did not pop up
if you encounter the same thing, switch to time trial mode & complete the very first level "learning to tilt" in the insane hills pack and it should pop up at the end...dont ask me why just be relieved it does =]
All credit to zeke1676 for the find on x360a, another achievement glitch prevented and a revolt subdued, great find my good man! =]