Thanks! I honestly can't say it feels like a lot IRL, i printed the size L due to my genetic predisposition to being a human bobblehead and as far as what you'd expect heftwise for a legitimate military/space helmet and what it would entail I think it ends up being fairly on the money, of course up to preference though on that. I'd say the two most important pro's (pun intended) to the FAST setup are:
-You can prevent wobble while wearing the helmet just like padding but while affording yourself circulation and extra space inside the helmet that would otherwise be filled, the posts hold the helmet a bit off your head and that "liner" he modeled has some vents in it which seems to make long stints in the helmet a bit less sweaty and claustrophobic (at least from the short stretches of time I've worn it around so far, i'll report back after I troop in it for a full day to see if this point really holds water LOL)
-The magnets used both to attach the lining and the front to the main helmet are pretty strong, having the lining there to sorta help rotationally lock it on the head where padding would allow a bit more rotational freedom certainly makes the removable face feature easier to use when being worn. If it wasn't there just given the experience of pulling it off and on with the magnets installed I could see it going from a one hand job to a two, because you'd have to hold down the back of the helmet as well to help separate it. Once again kinda up to preference there I suppose.
Hope this helps dude!