I use meters for my scale in Maya, I noticed that when exporting to any other program, the models were HUGE!!. With the help of others, it was learned that when modeling in Maya, units had to be set to CENTIMETERS to get proper size in AC3D or wings3D. By always using centimeters in Maya and meters in wings3D and AC3D, I never have to resize to work on things. If working metric, you always have to either increase or decrease scale by a factor of 10.
It depends on what you are working on. I can go from AC3D to wings3D with no resizing necessary. Going to maya, I have to increase scale 10x.
just something that has to be done.
omarsr