I think what you choose has to do with what works best for where you fly.
Check out this thread:THE FIELD BOX FROM HELL! aka The Ultimate Field box! under "Tips and Techniques"
hope this link works...
http://www.rcuniverse.com/showthread...light=ultimate
Most guys I fly with have something like this tool box with wheels. They bought them because it was a long haul from the parking lot to where we fly (we have moved from that spot). I have a Hangar 9 wood box and its perfect for me (I only carry necessities to the prep area). Everything else stays in my car until I need it, but then again, the parking lot is very close to where we fly..