When you buy a great printer you should always buy the best ink because bargains do not really work as well. However if you are not a professional or don't care how things look go for the bargains.
When people are willing to purchase all the cartridges bundled together they should get the best value. In the case with this purchase you literally only save a few dollars buying them all bundled verses buying them individually. The purchase is then only convenience not value. Why not add in the XL color cartridges so I the consumer feel that the extra money spent for all four cartridges in a value pack is "a real value" as well as a convenience. HP would probably capture a percentage off brand and self fill ink buyers by making the value pack a super value!