Good, but missing a lot
Being able to take control of the 4 agents from the show (and Aramaki in Multi) and 4 different Tachikoma was kinda fun. Kind of. The only difference in the people where what the looked like, and the Tachikoma only differed in how fast they ran out of ammo.
The music was exceptional Techno, especially during boss fights. However, during fights is about the only time you even notice the music. the rest of the time it's to quiet or calm to take notice of it.
The weapons had lots of variety. Of the same things. Every type of weapon handled the same. The only major differences were magazine size and how many rounds were fired with every pull of the trigger (semi, full auto, single, or burst). It was fun looking for all the weapons and getting each character's specific weapon (which all others can use after you unlock it).
Since that covers the best stuff, I should cover the less than stellar things now. The graphics were suprisingly good, it looked like a late PS1 game, but a lot of that was most likely due to the small screen. The voices were dead on too. Even the Tachikoma all had the same young girl voice from the show. It was nice not having to reassociate all the faces I know and love to new voices. Unfortunately that's were the good stops.
Anyone who looks below the surface will see that this game suffers from DWDC, Designers Who Don't Care. The enemies all behaved the same (just changed appearance), even the bosses acted like normal enemies. When you shoot someone, the only way to know if you even hit them was to hope you could see the blue flash from the bullet, and see if he fell down. Even worse is that it goes both ways. When you're being shot at, the only way to tell is the sound of the weapon firing. The thing that saves you most is the extremely high life you have and relatively low damage most of the weapons deal.
Over all, I'd say just rent this game. But if you absolutely must buy it, check the bargin bins at your local pawn or game shop.