I’m not sure when the last time was that I bought fuel based on pump price - it’s almost always on convenience - but it seems Woolies/Caltex is usually ‘competitive’ - prices here don’t change much, in town diesel goes for $1.50+ and premium unleaded for 1.65+ … 98 for 1.70+ - prices 20-30 cents per litre higher are common the further you get out of town - so when I travel to the big smoke I never shop on price - it’s ‘all cheap’ 
One thing about Coles Express - I personally avoid the local one like the plague. With all the stuff they sell, I find especially in the mornings that the majority of pumps are taken up by people who are using them simply for parking, not buying fuel of any kind - with no exaggeration. Waiting for a pump is one thing … waiting behind another car who stops at the pump and simply goes into the shop for his latte and the morning paper is infuriating.
