Sweet smell means you're burning coolant.

Change your LIM gaskets or wait till the top swap and hope you don't spin a bearing in the mean time.

My car needs 94 octane to be nearly knock free.

Filled up with 94 yesterday and i've seen at MOST 0.5* KR.

I guess the winter gas is finally gone, onto the good stuff

You only get better mileage if your car is setup to run on it (Or needs it to prevent knocking like my POS)