I love the Blueberry trainers, but that's primary bc on the adorable prints. :-)
We use normal panties at home, and when we go on a trip I put on two pairs and a pair of plastic Gerber pants. If she wets it is contained long enough for me to change it, and the plastic pants make it uncomfortable to wet in them, I would assume. We also have two car seat "piddle pads" (one made by the manufacturer - so safe with the carseat) as back up.
Depending on how close she is to full potty independence, it might be worth your time to try one of each. They may fit differently, feel different, etc. and sometimes its trial and error to find the right pair.