About 6 years ago I decided to retire our 40+ year old cast iron boiler with a Beckett gun, the prior season we used about 1200 gallons at near $5 per gallon. After a ton of reading I decided on a Buderus after having thoughts of Biasi with a Riello gun which a close friend had just bought. Super glad I went with the Buderus, I best him by at the very least 120-125 gallons a season. The first season we dropped to just above 700 gallons, I at that point insulated the very cold basement. The old boilers pipe kept it much warmer; the Buderus stack temp is very cool by comparison. I put 2” foam blue board on all the walls raising the temp 15 degrees F. Went another season and decided to ditch the separate oil fired hot water, I am now very pleased that that last season which was very cold I only burned 550 gallons. No question a tremendous savings. The cost was nothing to sneeze at roughly $10,000 that includes boiler, insulated chimney liner, new 330 oil tank and me insulating the basement. We are older than most and keep the day temps lows 70’s 65 night. IMO if you are building or upgrading do the research, the cost of upping your game is roughly 20% but gets real cheap as the years go by. Added note I had considered switching to gas, very glad I did not the US is starting to export gas with future cost projections passing that of oil. Buderus is a division of Bosch.