"The main benefit of using a refill kit is the savings. The average price for these kits is $10–$20 and they usually yield about three refills. Based on that, a person could be getting a new cartridge for about $5, versus the $25–30 they would pay at the store for a new one. There is also the environmental benefit, as you are reusing a cartridge that would have otherwise been thrown away after one use. [1]
The downside to refill is the time associated with it and the unpredictability. Refilling a cartridge can take 10–15 minutes for those unfamiliar with the process, and some may prefer buying a new cartridge to the effort it takes to refill. Also, ink cartridges usually last for 4-5 refills, but there are those that can only be refilled one time before they are worn out."
Answer
Here's an article that gives some pros and cons:
Pros and Cons of Inkjet Refilled Cartridges
http://en.wikipedia.org/wiki/Inkjet_refill_kit#Pros_and_Cons
"The main benefit of using a refill kit is the savings. The average price for these kits is $10–$20 and they usually yield about three refills. Based on that, a person could be getting a new cartridge for about $5, versus the $25–30 they would pay at the store for a new one. There is also the environmental benefit, as you are reusing a cartridge that would have otherwise been thrown away after one use. [1]
The downside to refill is the time associated with it and the unpredictability. Refilling a cartridge can take 10–15 minutes for those unfamiliar with the process, and some may prefer buying a new cartridge to the effort it takes to refill. Also, ink cartridges usually last for 4-5 refills, but there are those that can only be refilled one time before they are worn out."