i have read post after post and am unable to resolve my confusion. i hate to be redundant but have some questions. i am planning on and have room for 2-300 gallons of storage. i mainly do not understand the differance between pressurized and no pressurized storage. by the looks of the budget i am looking at using and insulating an oil tank or having a tank made out of 1/8th plate. is either system more efficient and what are the pro's and con's of each? again sorry if this is redundant but having trouble to sort this out.... thanks!