I must have forgotten to take my schizo pills when I was playing Clear Sky because it ended up being my favorite (note that I played SoC and CS very lightly modded with ZRP/SRP). I think every STALKER game is simultaneously flawed and stellar, just in completely different aspects. There's a theoretical superior STALKER game that could be achieved by combining the strongest elements of each, but the modding community is apparently too busy turning all the textures gray and adding a gazillion vendor trash items for m'immersion to produce it.
I wrote about my impressions of
SoC here and
CS/CoP here. In short:
- Shadow of Chernobyl easily has the best campaign in terms of areas, mission variety, pacing as well as the most robust artifact system, but the worst shooting mechanics and boring equipment customization and gear/economy
- Clear Sky has the best economy and equipment customization by far and the most entertaining shootouts, but is a mixed bag as far as the campaign goes (new areas are great but reused SoC areas are filler content for buggy faction wars)
- Call of Pripyat has the best shooting mechanics, simulated systems, exploration and artifact hunting, and side missions, but the equipment system is less interesting than CS and the main campaign is kinda bland with a huge lack of human firefights
Shadow of Chernobyl's problems predominantly come from it
being in development hell for years and cutting most of its planned mechanics/systems just to ship, but it definitely maintains the most foreboding atmosphere and the best balance of content regardless. The "hobo phase" sucks because your gun accuracy is so poor, not because of any interesting resource scarcity, but from there the game gets more and more fun, with tons of variety in bunker shootouts, mutant-infested labs, and navigational challenges with patches of anomalies. You're steadily introduced to new areas with tougher factions as you pick up stronger gear and I even think the final missions in Pripyat and CNPP are a blast (I joined C-Consciousness so I didn't have to slog through the escape sequence). I think people have genuinely forgotten just how fucking bad the gunplay is, though, particularly the
hidden damage penalty for firing in bursts that requires waiting 1-3 seconds between shots to actually get lethal headshot multipliers. The fact that artifacts are just laying around all over the place also makes the economy incredibly easy to break in no time, except there's also fuck all interesting to buy from shops until you can afford an exo-suit for the final mission, especially since better free gear is waiting for you in the next area.
Clear Sky has an absolute baller weapon upgrade system, which is really the main reason I love the game. Nearly every weapon has two mutually exclusive upgrade paths, gearing the weapon more towards CQC assault or towards long-range sniping. The paths are organized in a pyramidal structure, such that you have to buy all of the binary choice "root" upgrades in each path before you can access the next column. The cool part is that you can decide to buck the intended schema and mix and match upgrades in lower tiers -- I was rocking a silenced Viper SMG tuned for hybrid accuracy, handling, and recoil reduction for most of the game as my bread and butter weapon. The upgrades are reasonably expensive; CS has a more functional economy than any other vanilla STALKER game, which along with the exclusive faction rewards incentivizes doing side content for cash. Buying/earning new armor was a lot more significant with the varying number of artifact slots, though sadly the artifact effect minmaxing was boiled down to balancing against a radiation penalty which excessively limited your build options. Clear Sky also made bleeding and radiation hardcore as fuck which made the economy more relevant as well. The Swamp, Red Forest, and Limansk are excellent new areas (some of my favorites in the series) with some impressive shootouts, but most of the reused areas from SoC are just staging areas for the AI factions to wander around and get into fights, plus you don't visit any labs which were the highlight of SoC. The final mission in CNPP is unforgiveable garbage, and the Cordon machine gun segment is just dumb.
Unfortunately the upgrade system was gutted in Call of Pripyat, replaced with 90% linear upgrade paths for every weapon. Everything is so cheap that once you finally find the tools to unlock new upgrade tiers, you'll be able to purchase everything in the tier instantly. Finding the tools is a huge pain in the ass compared to finding flash drives for unique final upgrades in CS (which was much more optional), since there are only 2 tools to find in the world for each of the 3 tiers and there is literally no guidance about where to look. You can ask random NPCs about where to find the tools, but they'll just say "IDK, have you looked up your own ass lol?" There are a bunch of other positive changes, though, like consumables granting status effects, A-life being far more relevant to roaming gameplay in the hub zones, substantially more involved artifact hunting with great level design to unlock the potential of the refined detector system from CS, as well as great side missions with choice and consequence mixing combat, platforming, navigation, stealth, AI manipulation etc. rather than the procedural "fetch me 20 pseudodog tails" or "kill these faction guys" crap of the other games. What really disappointed me was how rarely you were actually forced into fights with human enemies; the bandits start out neutral for some reason (even after betraying them in one of the first missions), and most of the resistance you face when wandering around is from mutants or zombified stalkers. I liked all of the Monolith encounters leading up to and within Pripyat (plus the lab section beneath the hotel, I had missed those), but the final mission just peters out in an awkward way right as it's getting good.
I think a preference for any of the 3 games is valid, they all have their strengths and weaknesses. Though if you didn't like CS just because of the bleeding and the poor starting accuracy of the guns (which can be fixed with a bit of cash in the starting area), you're a loser. Also, Master difficulty doesn't "fix bullet sponges", you don't have to play on that shit (I did for all 3 games and it was a mistake).