Ben Lee , filling your own cartridges is great if you have the patience and the skill to learn how to do it.
The secret is first to put on free plastic gloves, the kind that come in every box of hair coloring. NOW you will never get your hands stained.
Next you must practice so that when you fill the cartridge you seal it with scotch tape so as to allow the ink to penetrate the sponge, preferably overnight.
When the sponge is saturated, THEN you take off the tape and make sure the cartridge is nice and clean BEFORE you put it in your printer.
SADLY, too many faults did NOT do this and let the ink drip down into the printer.
This would never happen if you first make sure the filled cartridge is NOT dripping and is clean.
I fill HUNDREDS of cartridges and print hand-outs and my hands are never stained, nor does the ink drip. I fill my cartridges for about 50 cents per time.
I do this because I do not charge our computer class folks for the handouts and don't mind paying the bill but try not to waste money either.
However, if you wish, generic refilled cartridges are about $5.00 so maybe that is a best buy for you and Too many faults.
Much good luck. You asked an interesting question because it is a fact that SOME people cannot even put a new battery in their watch while others (like me) do it in 5 minutes.
I have friends who pay big bucks to have some one put on new wiper blades on their car. If you know how you can do it yourself and save $20 every time. Same with ink-jet printers..