I intend to use inkjet printers and the amount of ink or the price of the Ink that will be used is not an issue. The printers wont be bought either, I am a computer technician so I have lots of them laying around. Power consumption is also not an issue. Also consider that colour documents print slower than black and white documents. The main concern is speeding up printing of large documents.
For example lets say the amount of time it takes after you click on the print button to the end of purging the head is 2 minutes and it takes another 10 minutes to print the 20 page colour document on one printer. That means it would take a total of 12 minutes to print the document.
If you had five printers working simultaneously the 20 page colour document would take 4 minutes to print. I think that is a much better printing speed then using one printer.