the danger with the 6 seperate carts is that when one is failing the print quality on whole document is affected ( i used to work on a tech support line for Small office equipment )
it's like a phone, are you planning on making 3 calls a week for 2 minutes each? then buy a credit phone, would you like eace of mind to know you can always pick up the phone and call at a low rate go contract
same applies to printers, we supply printers with a cost per page of just over 1 cent black, including toners service and parts, never buy toner again
we also have colour machines for € 100 a month including your first 500 colour prints regardless of toner coverage!