I realize I must be VERY lucky, as I've been taking my fuel bottles along with me on every flight, just like my stove itself.
I never cleaned them out, just emptied them the day before flying.
Now that I think about it, I've always taken along a full eyewash bottle of spirits to preheat my xgk (I find it easier / cleaner than using kerosene to preheat).
Never had any problems.
Must be my blue eyes??