Exactly what kind of models are we talking about? What are they made of? Also, how large are they?
A lot of it would depend on these three factors, although generally speaking I would probably go with lining the shipping boxes with bubble wrap or a similar packing material. Perhaps you could even fill the box with those styrofoam peanuts. Even then you're going to be looking at a small risk of damage, but lining the box with these materials could keep that risk at a minimum.
Michael - On my last move I had to transport 83 different Titanic and other ship models ranging from five feet long to the normal small ones. On the advice of my local museum I handed the task to a reputable Removal (well insured) company - I accepted their advice and gave instructions - shut my eyes crossed my fingers and hoped for the best.
Result was 100% safe delivery and installation and it never cost that much over the top either.
Mind you just ten days after I moved I found one of my wifes cats sound asleep on top of a model having done about £100 worth of damage etc. You cant win them all.
PS The cat is still alive!