Hello :-) What exactly is the difference between these cartridges for 71.60 vs. these? https://www.digitec.ch/de/s1/product/canon-pgi-580cli-581-multipack-c-m-y-bk-pgbk-druckerpatrone-8364831 Just the quantity, right? Or is there still a difference between the quality of 580 vs 581. Thanks for your answer!