Pod can be used to travel, but you risk getting killed and ending up at your medical clone location.
A corvette can be used for extra survivability of your pod, because then people need to kill you twice instead of once. Although it is free, the corvettes are really slow for travelling because of their bad align time and warp of only 3 AU/s.
A shuttle protects your pod from being instantly killed, while allowing you to fly at 5 AU/s and 2s align time. Perfect for travel, if you don’t need to avoid bubbles and smartbombs. In the case you do need to avoid those, grab a travel-fit interceptor.
Travelceptors are usually your best option to get somewhere alive, but the downside is that they don’t fit in a cargo bay of other ships as easily, require more skills and cost more ISK than shuttles. So if you can’t fit one of those or aren’t willing to risk that extra ISK, bring a packaged shuttle.