Fantastic work, I agree with Rebelreenactor it looks to clean... Beat them up, weather them a bit and they will look perfect, put some tracks in the sand and some grease on the wheels and the pivot points!
It might be also that the picture looks real clean, and in real life they look fantastic and very realistic... some of the weathering detail is lost in the picture maybe?
A+++ on the animation of the characters!! (I love the guy who is diving for cover with his "bazooka"), The camoflaging of the soldiers are spotlessly beautiful.......
From my own perspective, its easy for me to point out the stuff that is lacking, but far more hard to build.... When I first started building models, I remember asking "weathering?? you mean I have to RUIN my model after I just made it so NICE??"
Hehehheheh...