AK-400 is just an AK-104/105 with a longer barrel, rails and relocated rear sights. Might as well just call it AK-404/405 at this point.
More like Russia's said "fuck it", threw the cool old proto out of the window, and then tries a cheap attempt at making a Galil. It's like that they're throwing away their Lebedev to adopt a railed Makarov instead.
Even the old proto has more features (Enlarged mag release, thumb safety/selector) than this crap. But hey, who the fuck needs innovation when the rehashed "well-proven" ol' reliable design is enough, right? Just slap a couple of rails, integrate the sight with the gas block, relocate the rear sights, and done!
And the worst part is they featured THIS version of AK-12 on GFL. Blyat.