Currently...the theater is 'MOPP -' wich means all chem gear put away.
You have your choice if you want them in DBDUs or MOPP. I saw both (pixel?) BDUs and DBDUs on Marines over there.
The pixel uniforms are really soft to the eye. I would use really lighten down the colors on your figures for scale.
Here is a link to a fine example:
http://www.marcorsyscom.usmc.mil/sites/mcub/utility/index.html
On a side note (as far as Army went), not everybody had desert uniforms over there. Especially dealing with MOPP gear (chemical). Most of our chemical gear was woodland camo, with desert uniforms worn underneath. Some reserve and Guard units arrived over there, completely in Woodland Camo. I personally went back to Woodland Camo flight gear, to hand wash and dry my two desert flight suits.
You could possibly do a mix match in the group standing there, reflecting the reality of the supply system ;)