I received mine today (was supposed to get it yesterday, but weather delay). As Synz314 mentioned, this thing is "huge." As an owner of two Rocketeer Ant-Man helmets (first movie and Civil War), this one looks and feels "oversized." Maybe if I were taller, it would look better on me, but the scale just doesn't seem right, especially when you look at movie stills and see how the eyes are framed in the lenses, the helmet is BIG. I also found it bulky and heavy on the head to wear around.
Granted it's marketed as a toy, and if you want to match the movie, it'll require a good paint job. The top black portion is about right, but to get the stainless steel or metallic look all around the face and jaw, you'll need to paint it. Another problem I found is that the battery pack for the lights (3 AA batteries!!) is where the mouth is, and it just feels too close with not a lot of room to breath or talk. I also don't see why they bothered with blue LEDs or even have LEDs at all, given that the lights weren't prominent in the film (and I don't recall the helmet changing colors when he went giant-size like the helmet did in Civil War). They should've invested those LED lights inside the helmet, close to the lenses rather than doll it up on the sides and on the top of the antennas, and again, aren't lit in the last movie.
As for cosplaying with it, I'd pass on it unless you do some painting to make it look less of a toy mask that's sold in Target. It'd be like wearing the legends Iron Man helmet that doesn't match the rest of the body armor (color or styling). I've a down payment for Rocketeer's Ant-Man and Wasp Ant-Man helmet and eagerly awaiting that one to assemble and wear.
It's a good collectors piece and am glad I got it for that reason.