Quite an interesting article at NiftyStuff.com where they tested Canon BCI-6 cartridges, both genuine and compatible/refill, on various papers and subjected them to fading.
Their tests duplicated real life and although mostly US brands of ink were tested (as well as genuine Canon), the same results are to be expected from Australian equivalents.
The basic conclusion is that while compatible inlks can give acceptable results, the best was genuine Canon BCI-6 ink and genuine Epson ink.