Tomorrow S.H.Figuarts will be official release of STAR WARS First Order Stormtrooper Heavy Gunner.
Beside having heavy weapon, the uniform defer from the normal First Order Stormtrooper...
Here's a photo of Heavy Gunner with regular First Order Stormtroopers. You should see the difference.
If you are army builder, you would want to pick some of these up. It will be priced at 5,616 Yen.