Here are the main differences between these two settings:
The little stones on pave settings can get loose or dislodged if exposed to too much wear and tear. The prongs can become weakened over time and will need periodic check-ups. This makes pave settings not ideal for people with busy hands.
Pave settings emphasize the diamonds while channel settings highlight both the metal and the stones.
Pave settings are typically less expensive than channel settings, because they use smaller diamonds. In general, you can pick up a pave setting for at least a couple of hundred dollars less than a channel setting.