25km per litre?
people get same or less average as that of petrol, so if u r thinking about 25km per litre, that may be 25km per kg n not per litre
anyways in few weeks u'll have the average that we are waiting for 
lpg rate keeps changing, u got it for 110rs per kg, yesterday i went n they told me its 130rs per kg now, thats alot of variation
so even if u got it filled in lpg cylinder that must be from some specific shop right as this shop guy said that they dont fill it in cars