Okay, I've got the PS2 version now too and I'm really loving it.
I started with the D'cons, and I've not yet completed all the missions in the first area.
Let me take a moment to explain how the game actually operates, since this was not made clear to me in any of the reviews I read here.
The gameplay is divided into two parts. There are missions, and there is free-roaming between missions.
The loading screen before the game begins shows a diagram of the controls, and as soon as the game starts you're free to use them all. No restricted tutorial here.
The game starts in what I'll call free-roaming mode.
You're blackout, and you've got starscream encouraging you through the communications to go and show the army a proper decepticon welcome. There's a glowing green marker indicating where you should be heading for.
I however chose not to immediately race over to the marker and start 'welcoming' the army base. I chose something else.
That is, I chose to transform and run around blowing stuff up.
The desert area is not infinite, and if you wander outside the edge of it you are presented with an on-screen warning and countdown to being reset to the mission area. You don't die or fail in any way for leaving the area, you just get sent back in. The area is quite large though, so this isn't much of a problem.
After pausing the game and navigating to the right in the pause menu you are presented with a summary of the collectables. There are 5 grey D'con logos to be found, 100 yellow cubes, 4 challenges and 3 skills to demonstrate.
The first of these that I collected was one of the skill achievements. Destruction.
As soon as I started destroying stuff, a destruction meter formed of five logos appeared at the top of the screen. As my rampage continued, the meter filled. When it was full, I was informed that I had unlocked bonus content.
Now on the collectables summary one of the three skills was completed.
There was another skill for throwing things very far. This was kind of tricky since the throwing physics is not the same as that of real life. In reality, to throw something as far as possible you should aim at an angle of 45 degrees. However, in the game, aiming as high as possible yeilds the greatest distance when throwing.
The yellow cubes are scattered all over the landscape and are relatively easy to find. There are 100 of them though, so it takes a while, and I had to spend quite a while searching in helicopter mode to find the last 5 that I had missed.
The grey logos are again scattered throughout the landscape, but since they're grey and there are only five of them, they really don't stand out and are much harder to find. I found all 100 cubes, but only 1 logo so far.
The challenges are represented by larger cubes again scattered throughout the area. Upon reaching one you are presented with a summary of the challenge (destroy lots of stuff or push all the drones out of the ring or a couple of others) and the number of yellow cubes you must have collected before you are allowed to attempt it.
Those are all the collectables and activities available to you in free-roaming in the first D'con area (And probably the same system applies to all areas).
So at the start of the game you can either start looking for and completing those things, or you can do as starscream says and go to the green marker.
Upon reaching the green marker you're given a short cutscene and then a loading screen with a mission brief.
Some missions are time limited and some aren't.
Upon completing a mission you're returned to free-roaming mode as whichever character you were in the mission.
This means that when you do a mission that lets you play as Scorponok instead of Blackout, you get to be Scorponok in free-roaming afterwards.
In free-roaming you're always got Starscream in your ear telling you to go to the next mission, which is always marked with a green marker.
Previous mission are also marked, with yellow markers and you're free to go and re-play them as much as you want.
However, replaying a mission does not change your free-roaming character. So if you just did a Scorponok mission and you want to be Blackout again in free-roaming, going back and re-playing the first mission won't turn you back into him. You'll have to continue with the new missions until you get to one that makes you be him again.
I don't know how character switching is handled once you've completed all the missions in an area since I haven't done that yet, but I expect you will be allowed to choose your character from the ones that have mission in that area.
That concludes my explanation of gameplay. Now I'll get to the complaining.
The camera controls are annoying.
Right analog stick moves the camera. That's good.
There is an invert Y-Axis option. That's good.
There is no invert X-Axis option. That's neutral.
Pushing the stick right makes the camera move left around the character to give you a view of what is to the right. That's fine if you're playing a FPS, but for Third Person action that's the wrong way around. Coupled with the lack of an invert X option this is really quite a problem. I'm sure I'll get used to it eventually, but it would be nice to have the option of changing it to what I'm used to using in other games such as Okami and Legend of Zelda games.
When flying as a helicopter, the left stick controls your movement back and forward, left and right, while the right stick lets you turn left and right and pitch up and down. That's fine, except that there is no elevation control.
If you want to fly higher up, you have to look up and fly forward.
If you look down and fly forward you get closer to the ground.
This makes it hard to keep your altitude while trying to shoot targets on the ground.
I'm fairly sure that going backwards when facing up or down has the same effect on your altitude as going forward does. This seems somewhat counter-intuative too.
Those are my only complaints. Everything else is awesome!
Some people complained about not being able to transform while jumping. It's true, you can't, but I don't really find this to be a problem. Sure it would be a cool thing to be able to do, but it doesn't really bother me or have any negative impact on the gameplay as far as I've seen.
Of course, I haven't played any of the Autobot campaign, or any more of the D'con campaign that just the desert area, so I can't comment on the car driving controls.
For me, this is the best PS2 Transformers game.
There's something very satisfying about stomping around as a giant robot and blowing stuff up. Being able to transform into a helicopter and zoom around makes it even better!
Armada was quite good, but I had no connection to the series, the gameplay became boring after a while, you could only play as Autobots, and only 3 of them at that. There was no flying, just driving and walking.
Tataki was bad. It was cool that it was G1, but the gameplay was so poor. The script and voice acting was funny though.