Recommended FPS

CSGO

You mean F2P?

You could try quake live. It's free.

TF2, BF2, Quake, Unreal Tournament, Wolfenstein Enemy Territory, HL series, the Hidden HL2 mod, the previous CoD games(all way from CoD1 to CoD4), CS, Garry's mod, Arma, and Far Cry.

For now, it's all :P

America's Army Proving Grounds Beta. Completely free, no micro-transactions, friendly community, very tactical. Bit of a steep learning curve for beginners but very fun overall.

Cabal Online. http://cabaleu.estgames.com/en

Quake 3 Arena

Red Orchestra 2

There are a few new ones coming out like Unreal Tournament 4 (summer 2015?), Toxikk (early 2015?), and Reflex (new on Early Access).

MW1

Blacklight: Retribution (definitely not P2W)

Alliance of Valiant Arms (still not P2W)

Insurgency.

Insurgency is what you are looking for.

Enemy territory (ETpro), too bad it's not on steam.

Metro 2033, Far Cry 3, Half-Life 2, Deus Ex: Human Revolution, Left 4 Dead 2, Killing Floor, F.E.A.R., Borderlands 2, CSGO.

borderlands

Hard Reset. Had a good time with it :)

Quake Live

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