Use at your own expense. Octane boosters are really not gonna pull extra hp, might even decrease it, and ruin something in the process. Last I read, bmwusa doesn't approve of any boosters, and as others I kind believe putting octane boosters, is like putting a Lamborghini aventador badge on the front of the car and saying it gained 500 extra hp.
Btw, if you need more power gains, try Dinan or some reputable tuning company, otherwise enjoy your sweet ride!
BMW and Mercedes Build Beta Products!
Lexus build Release Candidate Products!
Why does this matter?
CAUSE EVERY TIME someone says Lexus has better build quality, one should consider what Toyota their Lexus Engine and chassis platform comes out of and how long that part has been tested in the real world!