I always take a backpack when traveling. I find them to be the most useful piece of luggage that I have once I arrive. The first trip that I ever took with my Ghurka was to outer space. Or at least as close as most of us will come to it. I packed up everything I needed for my day in the backpack and was off to Cape Canaveral. It was a fun day of exploring and discovery about the development of the US space program. And my Ghurka provided all of the supplies that I needed throughout my day.
The backpack provides all of the storage that I need with convenient pockets and space that I need for storage of a day's worth of fun.