While replacement ink cartridges tend to be fairly expensive, a lot of people prefer to save money by have the old cartridges refilled or getting a do it yourself home ink refill kit. The desire to save money on ink is understandable, especially if you do a lot of printing. But: Can cheap ink be too cheap?
That is a question explored by Jeff Bertolucci of PC World in his article, where he concludes that Cheap Jumbo Ink Refills are Too Messy to Recommend. He ordered a "jumbo" ink refill kit on Amazon ( 20 ounces!), which he saw available from multiple online sellers. The kit is supposed to be for universal use.
Bertolucci, who refers to himself as "PC World's Refiller"- so he oughta know, found that 2 different jumbo refill kids were too messy, and the cheapest of the ink may not be worth using. He got better results in the past from remanufactured inks and the Costco ink refill service.
In my personal opinion, I'd rather not MESS with the DIY ink refills at all. There are plenty of online vendors of cheap ink cartridges, and you can often find high quality OEM or generic replacement cartridges at a very low price. With all the online price competition in regular ink cartridges, there isn't much of a need to even consider the refill alternatives, especially when it comes to color ink.