My Canon Pixma Pro-100 needs new ink cartridges for pretty my all 8 colors. The OEM (Canon) brans are very expensive. Debating whether I should suck it up and buy OEM of try a third party.

I've never used 3rd party ink so I don't know if there are any ill effects. Some HP printers know when you've refilled a cartridge and won't print with it. You might want to research if your printer does that too.

I know with my Canon 100 pro, if I want to refill my own cartridges, I need to buy a "chip resetter" so the printer will know how much ink is in each cartridge.