[Cory]

Originally Posted by Will Hanashiro

i also would not recommend casters. four wheel drive is sufficient, six wheel drive may be going overboard. if you're looking for on-the-dime turning, why not try a trick wheel? for those of you who dont know, a trick wheel is a normal wheel, but with a whole lot of miniature discs going around the perimiter. the miniature discs allow the wheel to slide sideways, yet they provide sufficient traction for rotating foward.

Search for "omniwheels" to get more information on such a "trick wheel"

Cory