I was hoping this would solve the biggest issue Arma 3 has: really bad AI. Sadly, it is about as dumb as Arma's AI while offering you way, way less options and customizability and variety. The most effective way to play is still to equip a long range scope and simply snipe all the enemies who are randomly strewn around the maps. They will never find you, look for you or even get into cover. Enemies will casually wander around in the open even if there are bodies of their comrades everywhere. Of course a lot of games can be ruined by playing them in a boring way but the issue is that I don't think the "intended" way is much better. Since enemies just wander around there is no real tactic or strategy you can use as a team. The level design is just too open and the AI too random to really feel good.
Compared to Arma it doesn't have things like vehicles and teammates which would genuinely be fine if it had decent AI.
But as it is, there is no real reason to play this over Arma's Dynamic Recon Ops mod if you want big open maps or SWAT 4 if you like tightly designed levels and you can probably get both of those games for less than 20€ by now

The game's story is based on a legitimate unit known as the Special Activity Division, which is part of the CIA. The mission of these troops is to carry out covert operations for the United States of America. The soldiers operate in enemy territory. At the same time, the SAD military is not an official organization, so they don't have to follow the rules, meaning the unit has almost complete freedom to choose the methods of completing a particular mission. The game is intended to be played exclusively in multiplayer and on PC and revolves around small skirmishes between squads of perfectly trained soldiers. During the development stages, the focus was on realism, so your troops' health does not regenerate, serious wounds are often fatal, or minor injuries severely limit the character's movement abilities. The physics engine calculates characteristics such as ballistics and the effective penetration of bullets, which are determined by various parameters such as distance from the target, speed, wind direction or the type of material hit. Players can freely customize their soldiers; simultaneously, each type of armor, weapon or other piece of equipment has its own weight, which affects the character's mobility. The arsenal of weapons is in no way artificially balanced, aimed at maintaining the maximum possible level of realism, and all equipment is given to the player from the first match.