It is possible to [Dash] while Prowling, for a total of 105% standard running speed.
Prowl makes Stealth runs possible, but watch out for stealth-detecting mobs!
This can be useful in some dungeons if your allies fall to a lower area and dies or is killed. You can sneak past the mobs to rez them instead of them needing to run back or wait for the group to fight their way to them.
Prowl is often used in PvP games to get to goals undetected by enemy players, such as the enemy flag, an unclaimed territory, etc.