composite is the only way to go....I prefer Fiberon decking, my deck is 16 years old, still looks new....non skid when it rains...easy maintenance I schwab the deck once a year in the spring with water and bleach let it dry and will look brand new....recommend pressure treated joist....my neighbor used brazilian hard decking has replaced and patched a few times....
If loading composite on vechicle B careful when layered on each other tie it down good or it will slide onto the road when U apply your brakes....