Great idea (full gun customization), absolutely god-awful execution. Stay away from this game, don't even watch it. It's completely unoptimized, even on minimum settings and on a powerful PC it has huge lag spikes that reduce the frames to 2-3 per second. Completely unplayable. The munition physics are super iffy: your movement seems to affect your own bullets in very unpredictable ways, and the bullets themselves behave pretty oddly. The enemies are very boring and either piss-easy or instant killers. The quests are completely pointless, no reward from going to point A to point B over and over again. The characters, environment, and pretty much everything else looks ugly as hell. The guns themselves look passable. The map seems to have been made in 20 minutes in Unity, with only the most basic tools: the terrain is composed of jagged edges that act as "mountains" and "hills", where the texture stretches like your grandma's soggy ass. I thought for a moment there was going to be some exploration to find special parts for your guns, but all the nooks and crannies are completely empty and pointless. Not that exploration matters much as you can climb any slope or wall with very little trouble, making most travelling trivial.
In short, it's not fun, it's not even worth experimenting with, it's ridiculously slow and veeeery boring. It's clear the dev had an idea and quickly implemented it into a game he slapped together in a week or two, but without at least one or two more years of work, I don't think this is even worth considering.