The problem with storing petrol/gasoline is not the stuff itself (the governments should know, as they have wtfhueg emergency stockpiles of it), but the recently added alcohol content. 5% doesn't matter much, so 98E5 (99 V-Power, any proper fuel) will stay good much longer (not that I would even put that 95E10 crap in mah car). However, 10%, as in 95E10, it does matter, because it starts to break down the molecules in the petrol and actually form a sort of resin, which will clog your filter and/or injection if ingested by the fuel pump.
Reportedly, sudden temperature changes, especially going from minus to plus Celsius or vice versa, accelerate the process, so in typical Southern Finnish winter weather, 95E10 can be ruined within WEEKS, as opposed to several months for E5 or even years for alcohol-free petrol.
