Many people believe that using ink refill kits will save them money. Unfortunately, most people look at the price of a refill kit and a price of a new printer cartridge, and go with the refill kit, because it's usually cheaper. Here's some things people don't consider:

1. YOU VOID ANY MANUFACTURER'S WARRANTY WHEN YOU USE A REFILLED/OFF BRAND CARTRIDGE. These cartridges simply aren't the same, and all manufacturer's will void the warranty when you use a refilled or off-brand ink cartridge.
2. You damage the cartridge when you refill it. Any debris left after either drilling or using a needle to inject the ink can get into the ink, and clog up your printhead in your printer. If that gets clogged, you can't use your printer, and it'll probably cost more to fix it than to get a new printer.
3. There's not as much ink in the cartridge as there was before. Refill kits do not fully fill the cartridge, so you don't really save money when comparing how much ink you use. They can also leak ink, ruining the inside of your printer.
4. The printer is designed to use the manufacturer's specific ink, not the generic ink that refill kits use. Again, this can cause clogging and other defects, and you will raise the price greatly of your printer maintenance.
5. Many more remanufactured cartridges fail out of the box compared to genuine manufacturer cartridges. Not surprising.

There's a whole slew of reasons why it's better to stick with the genuine inks rather than save $3 and cheap out for a refill kit or remanufactured cartridge. These are just the main ones. Hopefully you take this into consideration next time you shop for ink.