So i'm not a constant user of my chainsaws but things can happen around the house,like a few trees leaning over the fence or something so the chainsaws can be sitting for a few months and suddenly go trough 4-5 tanks of gas in a day,now i mix my fuel at a 25:1 mix meaning that i put 25 ml of oil in 1 litre of gas but the amount is not a problem the oil is.I don't know what oil i should use.I have Husqvarna LS+,Stihl HP and Stihl HP ultra and i dont know what should i stick with.Any advice?