The countless flaws spoil a supposedly great game.
There are many similarities between both of them, so it was only natural to assume that Mercenaries would inherit all the same flaws as its foster parent. This is not a hundred percent truthful assumption however. Mercenaries does have a good cause, yet lacks both at execution and motivation none the less, just as GTA series did.
Mercenaries also does have atmosphere, and lots of it. You really do feel like being a part of the conflict. Soldiers shooting at you and each other, both air and ground support showing you their ugly sides more often then you would wish for, building collapsing into million tiny little pieces, cars exploding with brutal and undefeatable force. All that is shaping an unforgettable atmosphere. Which is probably one of Mercenaries' strongest points. Music however feels out of place, something anyone familiar with the dreaded Star Wars series would recognize in an instant. All the same passages are there. But luckily it doesn't ruin the atmosphere that much, so it is forgivable.
Graphics are terrific, especially for the PS2. Yet another stronger point of this game.
Now let us get to the numerous flaws that bring this potential masterpiece on its knees.
The most obvious shortcoming is off course the ridiculously retarded AI. Especially the ones of you allies. Tell me please: what idiot would ever try and shoot a person with a rocket launcher?!? Ironically enough the AI has an superhuman ability to spot the player from at least one mile a distance, and shoot him without almost ever missing from all heavy projectile weaponry starting with RPG's ending with the anti-air (!) artillery. That is not all our telepathic opponents can do. Officers can unmask a disguised helicopter flying on a 250 meter altitude in an instant. To make it even more annoying Pandemic decided to make us lose our cover every time the horn was used, thus annihilating the whole purpose of disguise completely and irrevocably. It has its uses sometimes however, but those are scattered far and in between and exist completely freely of the non-existent stealth element. I wonder: what is the only female character good for besides her pretty sex appeal if her specialty is sneaking in a world where covert operations have no meaning at all? But let the philosophers decide on that. I will focus on the core of the problem as any convinced pragmatic. Why in the world was the stealth factor minimized, if not eliminated completely in the first place? Isn't that what the MGS series taught us about besides her fuzzy logics? In a one man operation the concealment plays a critical role, does it not?
Now about the supposedly vast world. There isn't much to do in it except doing main "story" missions. By the way - there isn't much story in this game anyways. NK, lots of factions facing each other, big bad wolf general Song with a 100 million reward on his head (alive, half if killed). And you in the middle trying to save the day and get those wretched bloody papers.
So there isn't that much to do, except do the missions. Side quests and collecting special items does not earn you much, so better leave it be and concentrate on the missions, which are pretty variable. But are still scripted and dumb as in GTA. Especially when it comes to baby-sitting.
The air support is mostly useless, since the anti-air defenses are mostly in-place, executing their superhuman capabilities of shooting any air threat that feels brave enough to occupy the hostile air space for more than two seconds. Bomb raids are mostly useless and are way too expensive to be any cost effective. Luckily sometimes the circumstances force our hand on using them. But those sequences are once again scripted and are too rare to make any difference.
Tanks get blown up way too fast. Even the Abrams tank. Thus their uses are very limited. The vehicle I found myself using the most was off course the NK disguised helicopter. Just as any helicopter in this game this one can get to a high altitudes that protect it from the air defenses. Which is not realistic at all. I guess this game was meant to be played by both legitimate cheating and non-legitimate one. NK disguise is useful sometimes if there are no officers around, and it also has a homing missile launcher which is sometimes essential to the mission' success.
Lightly armored Humvee on the other hand is much more useful than the heavy armored "pantzer batallion" due to its relatively high speed. And the street racer is indeed a very fast vehicle, ideal for breaking the blockades and lightning fast operations, that usually end in its own destruction unfortunately. Plus it's just so much fun to use.
Almost every fire arm in the game is negatively broken, with a very low accuracy rate, even at the point-blank range. The sniper rifle is accurate, but still useless most of the time, since your scope begins to vibrate wildly every time you're hit. Funny, because if you don't use the sniper scope the regular one never does such a thing. Shotgun is miraculously accurate, even at high distances, and picks up quite a punch with mostly a one-hit kill.
Grenades are useless, since opponents spot it the millisecond you press the L1 button, and begin running around it like morons. Rocket propelled grenades and anti-air launchers are useful, but their ammunition is very limited.
Firearms sounds are abysmal. Shotgun sounds like a tin can the is being used instead of a foot ball. Mounted minigun sounds more like the same tin can filled with rice. Explosions sound pretty nice though.
All and all we can see clearly that the firearms didn't get much attention. Which is yet another gameplay flaw.
Difficulty level is pretty high, but only due to the supernatural opponent abilities. Even whilst using the "cheater's special" the portable air-strike, missions can get annoyingly tricky. Which is bad. Playing the same mission over and over again is boring and irritating. Checkpoints during missions could have saved the situation, but sadly enough there are none.
Time to give birth to a conclusion. Whilst an unforgettable atmosphere of a war-zone, great graphics and a vast world. A supposedly good gameplay spoiled by a vast number of flaws that push it all together into a vastness of the abyss, a terrible story and an inability to deviate from the main missions due to the lack of motivation. We get a product that's just above mediocrity. Yet bears a lot of potential and is better than the acclaimed by the masses GTA series. So the final conclusion is: if you are willing to sacrifice your pride as a gamer by using cheats just to play this game trough and see what it has to offer, please feel free to do so. But only in a rented package.