im doing a fondant figure sitting on the top tier (2 tiers 6" on a 8") with her legs hanging over the edge. Im undecided if i should sit her on there before the customer picks it up or should i have them place it when they get it home. Im wondering it it will travel well. I dont want it to fall off or tear through. i do have a toothpick in it to help it stay in place, what do you think?

To me it will depend on how far it will be driven and if at all possible to know what kind of driver it will be.
They certainly are not hard to place so I probably would not place but send in separate box for customer to place.

I would suggest waiting until the cake reaches its destination before placing the figure. The potential for disaster is too great during travel for an embellishment that takes such effort to craft and is relatively simple to place on at the last minute. Better safe than sorry!