We have a trunki for my son, its good for bringing toys on the flight and him being responsible for them, but 90% of the time, guess who is carrying it...yup, ME. He doesn't want to ride on it too much or pull it along. I got some Trunki stuff at Quality save over the last few weeks, a backpack (that my son loves) and a pillow, but not the case.
I think they are great, and if your kid will ride on it, it does make going through airports easy.