Since I can't in good faith give clear sky best in series due to being broken, this is it.

User Rating: 8 | S.T.A.L.K.E.R.: Call of Pripyat PC
Like I said above, to me clear sky is the best in series if you can get it to work, but this game over the improvements of SOC was a damn fun game I thought, I got a lot of hours out of it, got to tweak my gear and guns. Monsters where about on par with the first 2, about the only thing I miss from SOC that I didn't get in Clear sky or COP was the feeling of being in more open non linear world, not sure if that makes sense to some or not.

I really like this series to be honest, if the programming wasn't so bad, I'd put the series in my top 5 all time.

Lots of mods to be had for replay value, I tend not to use them, but I hear they are fun, I'll replay them without the mods and just try different stuff that I didn't do before kind of like what you can do in oblvion or fallout series.