Woah-shit
As far as artistic ability, nice stuff.
The Ruskie blew the Kraut's face off xD
Anyways, only beef on authenticity is:
Russians wore Russian caps
The German helmets did not have an Iron cross, they were either bare, or had the Waffen SS (Lightning Bolt) symbol.
The gas masks were fabric, but it seemed you were going for some sci-fi stuff.
All the rest is some Top-Shit, good job.
8/10