Whether you use cheaper third-party inks or your printer's official brand, the results can vary greatly depending on the paper you use. In general, there are two paper types: matte and photo paper. The former is the stuff you use on a day-to-day basis because it's cheaper.
Between brands, the differences are few, but if you're an Epson, HP, or Kodak customer, you should definitely find a matte paper with the ColorLok logo.
ColorLok makes your prints look better, even on plain paper. Paper with this logo has been pretreated with a solution that allows colors to look more vivid; blacks seem deeper and images appear sharper because of less horizontal bleed. This is especially true if your printer uses pigment-based inks. And if you enjoy printing double-sided pages, you'll find that you get next to no bleed-through, regardless of paper thickness.
The picture above demonstrates ColorLok in action. We used generic craft paper and placed a drop of ColorLok solution on the surface. Then, we added a drop of black pigment ink on top and did the same to an area of the paper without ColorLok. When you flip the paper over, you can see the difference. Even though we're only using cheap craft paper, ColorLok holds the pigment higher on the surface and reacts with the ink, causing it to dry faster.
Even if you own a printer brand other than HP, Epson, or Kodak, you should see some gains with ColorLok. The picture above shows the printing results from a Canon MG5220 on various matte papers. Notice how the text appears darker and sharper on the ColorLok-treated papers.
As a general rule of thumb, ColorLok helps increase ink saturation, which results in more vivid colors.