I know the sign you've described. Here's the difference between the two "travel" signs, as I observed their use:
TRAVEL (using ZZ hand shape), for describing travel from point A to point B, or on a pathway to a destination. Traveling to a place.
TRAVEL (using twister type sign), for describing movement without a destination, such as when sight seeing in a city, cruising the mall, touring a museum. Traveling around or about a place.
