Well SA Warranties and Motorite do sell motorplans for almost every car i think, with terms and conditions, however they are very expensive, the best thing that you can do is extend your plan with bmw if possible.
On my meg, i had an SA Warranties plan on it, they paid 100% never gave any issues, only thing they didnt pay for were the sensors and mountings, they said i needed a warranty to cover those things, but everything else they paid for. Honestly bud, i say stick with bmw, its your best bet.