Many sellers, including ourselves, offer discounts for buying combo packs or large quantities of product. Bulk buying seems like a great deal at first look, but here's something to consider:
Even if they're sealed in their original packages, cartridges can lose some of their print quality over time. The shelf life of a typical cartridge is 12 to 18 months and sometimes more. If you do a lot of printing and think you can go through all of those cartridges before they reach their shelf date, then buying cartridges by bulk is an excellent deal. However, if you do not print very often, it may be best to stick with single packs.