The helmets that come with these guys are a pain in the *** just like Loki's
They come assembled already but are not on the figure sculpt, so you have to break them down into 3 pieces and re-assemble them for the figure to wear.
Sounds simple, but the helmet for my foot soldier is a stubborn pos. I can't get it to disassemble, may have to try the hair dryer trick when I get a moment.
Like they already mentioned, the FS helmet is only two pieces and actually comes apart as it should; the helmet can be worn alone and just the face mask comes off like the reveal in the flick. That's something that HT actually improved for accuracy from proto to production. The helmet in the protos didn't have the guard that covers the nose bridge as it appears in the movie but they added that for the production pieces. Still not exactly accurate but better than the protos IMO
As for the Commander's helmet, I found it really easy to do in two pieces. Like keep the top and one side together, fit that onto the sculpt and all you have to do is attach one side instead of snapping all three sides around the head