Now that I've beaten the game, I feel ready to give my complete opinion. There are two things I'd like to say about this game:
1: This game is tense, exhilarating, and terrifying.
Receiver 2, to put it simply, is the Cook, Serve, Delicious of first person shooters if Cook, Serve, Delicious was a psychological horror. Every function of each handgun is bound to its own key. On paper, this sounds incredibly clunky. You're right. The fun part is mastering it to the point that it isn't. The reason this game feels so tense the more you play it is because you have more to lose and it's so incredibly easy to lose it. It can take as much as an hour to rank up once, and all it will take is one bullet to take you right back down. This is the type of game that will have your heart pumping when nothing is happening, because nothing happening means there's something about to happen. This is the game that will make you afraid of blue lights and hearing 'Beep!' when you weren't expecting to will make you panic. This game will make you beg for mercy as a chunk of metal on the wall holds you hostage in the bathroom. This game will get you pumped when you pressed evvzzzzzzrf (or e5zt) in quick succession and you didn't even have to think about it. This game makes you want to press t+r incessantly, just like a jrpg makes you want to save incessantly. This game gets your heart pumping from excitement, stress, and fear.

2: This game is a great supplement to learning to handle firearms. However, it ABSOLUTELY is not a replacement for general training.
I am already trained in how to properly and safely use firearms. I can safely say this game does not teach you how to do this. However, if you're already trained, you'll be able to find your way around the handguns in this game without much, if any, advice from others. For example, Since playing this game, I've had the opportunity to fire a Glock 17, a S&W Model 15, and a Colt SAA. I was able to proficiently use all three of these firearms without any help, because I played this game enough to know exactly where every part was, what it did, and what steps I needed to take to use them. The secret firing range level might actually make for a really effective teaching aide.

If this game seems even remotely up your alley, buy it. This game is incredibly underappreciated (as are the lovely developers who made this game). Be prepared though, this game takes no prisoners and is quick to punish newer players.