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