PFS inks have worked well in my Canon printers for several years.
As a tip, Canon cartridges can be filled much more quickly and easily using eye droppers instead of hypodermic needles. Simply drip the ink on the sponge on the bottom opening of the cartridge. The "empty" sponge will hold 3 or 4 milliliters of fluid. While this method will not fill the reservoir at the other end of the cartridge, it can be done "on the fly" much more quickly, and does not require drilling any holes in the cartridge, installing plugs, and cleaning up a significantly larger mess. In short, filling cartridges with eye droppers is not a labor intensive project anymore.
This tip was reported to PFS several months ago, but there was no response.