Depends. How old are the machines? If you think they will need upgrading in the next 6months -1 year (to keep up with the requirements of whatever you use them for) it may be cheaper in the long run to leave them. After all, PCs are heavy and will cost alot to ship 5 of them.
Best idea is to scrap them for parts IE decent motherboards, ram, and video cards (which can be packed safetly in a suitcase) and then build your own rigs once you get here, I feel as though that would be the least costly option.
But they are your machines, its up to you how you feel about them.