So what we have here is your typical Koei/Omega Force collaboration. This one is called Dynasty Warriors Gundam. If you are expecting anything besides Dynasty Warriors gameplay with a Gundam skin then number one, you are stupid and don't know how Koei works, and number two, go ahead and stop reading, this isn't the game you are looking for.
This game plays exactly like every other Dynasty Warriors made since the second one. You pick a guy, read a couple lines of texts that might possibly be voiced (in this case it is) which only serves as an excuse to go to a battlefield and mow down tons of dudes. I had no previous knowledge of the Gundam universe, and after playing this game, I still don't know shit about it. There is an Official mode, which covers the stories of 6 characters from the Gundam universe. And when I say "stories" I mean a couple missions preceded by a few lines of text. Each story starts with about 6 lines of dialogue and then bam! Off you go to murder stuff.
A lot of the stages are shared between the 6 characters, and the most any of them have is 5 stages, and 2 of them only have 2! Laughable. There is an Original mode, which is an original (see what they did there?!) story that Koei made up. Basically, a planet appears and is heading toward Earth to presumably HULK SMASH! it. So off you go to save it. You have 16 different characters to pick here, and there are a lot more stages between them, even though they are usually paired up in groups of three that share the same path.
There is absolutely nothing here that deviates from the DW formula. Recycled stages, terrible dialogue, terrible translations (according to the gallery, Domon and Rain used an attack that has the word love in it twice in a row! And Domon's special attack is called burning...FINGER!!!! Yeah it's bad) button mash combat, pilot skills you can choose from, and items you can equip. There are fields reminiscent of the DW empires spin off, but there is no enemy main camp you have to make a supply line to. The AI is smarter, or maybe more appropriately, cheaper, in this game compared to most DW games. They are far more aggressive and love to attack you right when you get up. Not necessarily a bad thing, since the AI is generally stupid in this series, but worth mentioning.
The graphics are your typical DW as well. A decent amount of units on the screen at a time, but you have a terrible draw distance and the models don't look all that good. You have some story action, a versus mode, and a gallery. Again, typical DW (see a pattern yet?)
Honestly, if you take away the Gundam lore, the fact they can dash, and the guns, you could easily mistake this for the next DW game. There is nothing else to say. If you want DW goodness in a Gundam skin, get this game. If you don't like DW, don't.