Caltex, Shell and CRC

I used CRC before, the cheapest but not poweful, $400 for 300km
Then changed Esso, $400 for 290km, but earned Smile points can move to Asis Miles.
Later I changed to Caltex, it's powerful, more expensive per Liter but $400 for 300km, so used until now.
Shell I didn't use since all friends said it consumed very fast.
$595 for 290km is more expensive than mine, more than $2 per km,
99 Premacy should be 1800cc?
Mine is 97 BMW 318i, also 1800cc, just $1.3 per km.
But different car types and driving skills and habits also affect the consumption, so than it is hard to compare with others.
I suggest you change another fuel supplier, to compare by yourself.