It is a simple yet engaging game. As a gun enthusiast in a country where the fire arms and ammuniotion laws are very strict, this is a nice way to see closely my favorite weapons.
The graphics are pretty decent, and could do with an upgrade, but the detail provided is good.

Yes, the bad part is that you have to grind for XP to unlock new weapons and the weapon tree is not fully visible, unless you pay. But guess what? This is a free game and you can play free for as long as you want. Most of the guns are availabe without having to pay. I don't mind the XP grind since I haven't paid a cent yet, nor did I feel the need to do so. The people who made the game, have to get paid somehow, so I don't mind the microtransactions.