3rd party ink usually will not work properly on your printer because the printer was never calibrated for that ink. hence, the colors will probably be wrong. (if you don't care, i suppose you can still accept bad colors.)
also, the ink may have components that may react badly to your printer. (cause clogs, eat your PCB, etc) i wouldn't trust 3rd party ink.
in the end, you have to decide if you can accept that versus the amount of money you can save by buying that ink. is the price difference worth it?
agree on wat u say...cos recent PC shows i see n hear ppl buying 3rd party inks all over...
check its ink price already...still can afford original n should last quite sometime b4 need replacing..