Years ago, I would have said refill, as it worked well at the time and was pretty cheap.|
Tried it again recently, it was difficult, messy, the results weren't very good when it was first reinstalled, and then the printer rejected it anyway.
What I have found works well instead are third party or remanufactured ownbrand cartridges that are marked as compatible for your printer. They're not available for all brands or models, but they are at least for mine ... seem to work and last just as well and as long as the official ones, but are about 25% less. It's not the drastic saving that refilling offers, but it does help cut down the silly price of inkjet printing at least.
Alternatively, consider swapping for a cheap laser? For starters, toner doesn't dry out if you leave it a month without using it...