[mynameisgrax]

For flying units, and other oddly shaped models, I'd definitely use foam trays. You don't need an official army case though, unless you really want one. Any box that's large enough to snugly hold the foam trays will do. In fact, with the more fragile models, I've found that the 'snap shut' army cases can actually be counter productive, since they squeeze the models, sometimes breaking them.

Use foam trays, and carry them around carefully, in whatever method is most comfortable for you.