i took a little over 4 yr break from flying after my daughter was born, when i got back into flying the gallon that had been opened previously (only had about 8oz out of the jug) flamed out constantly but the unopened jugs were fine, flew perfectly. all were Cool Power 30% heli fuel. all stored in my 'junk room' that has ambient sunlight and gets fairly warm during the summer months.

kc