Is it safe to mix methylated spirits with isopropyl alcohol?

I have about 200ml of methylated spirits and 500ml of 100% isopropyl alcohol that I want to mix together in a plastic drink bottle. I will use it for fuel in an alcohol burning stove while camping. I can't seem to find any other information about mixing them so...

1. Is it safe to do so?
2. Is a clear plastic drink bottle OK to keep them in? (worried about melting the bottle - adverse reaction)
3. If it is safe to mix them, will I end up with a more flammable mix?

Thanks for any help!