I have been hearing lately that you are not suposed to store U4 in a plastic jug that it looses its oxy content if it is not in a metal can. I have been storing it in plastic scince i started using it a year ago. Does it really matter? Are there any decent metal cans out there that dont leak all over and are ease to fill the bike with as well as transfer from the VP can. Just wounering what you guys use.