Asok,
I'm contemplating that exact thing for travel to conventions and such. The way I look at it, I'm going to pack my jet pack, rifle, gauntlets and knee guards in a custom case, made from plywood and foam, covered in black vinyl with amplifier-style chrome box corners.
All the remaining parts will fit in a small duffle/gym bag.
As for the helmet, I'm searching for something that the helmet will fit in, yet still have room to pad the insides. Even better if I can find something with a handle on top. If that doesn't work, I will build a small box out of plywood, and cover it the same as the bigger box.
At the airport, I plan to check the other two items, and bring the helmet box/bag as carry-on.
One note, however. If at all possible, make sure your RF stalk is either collapsible or removable. Don't want that puppy breaking off by accident.
I'll keep watching this thread, because I'd also like to know what others are using...