For your booth at a trade show, the greatest long distance visibility that you can create is with a hanging sign. So by all means, if you are allowed (usually you must have a island space) consider such a sign. However, when you go out to design the sign, consider these key life cycle cost affecting variables:
If you are using labor from an EAC, or in some cases the general contractor to assemble your exhibit, you need to keep in mind the minimums required by that contractor. In general, there is a 4 hour minimum charge for labor (whether teamsters, carpenters or stagehands) and 1 hour minimum charge for electricians.
There are some very strong opinions about whether or not to ship into the advanced warehouse when moving your exhibit into a trade show. At most shows there is a premium charged for this service, but at almost no show is the premium so high that you should completely eliminate the possibility of using the advanced warehouse.
Instead, I usually base this decision on how tight the installation and dismantle set-up schedule is.