Genuine Canon GPR-56 CMYK Toner Cartridges and similar items

I've purchased these cartridges many many times over the past several years. They are a great deal, considering the price and the volume of ink (times 2 because there are 2 cartridges).
Every once in a blue moon, 1 cartridge has arrived with ink leaking in the sealed plastic bag. This is really rare and I think it comes with the territory (inexpensive ink cartridges). I obviously don't install the leaky ones, and I've never had a problem with leaking inside the printer. They still get 5 stars from me. I use a lot of ink and these print well and the ink lasts. At this point, I wouldn't even consider looking for a substitute.