I love the DS version... though I never finished it... and since is my brother's DS, I barely ever got time to use it.
I must say I'm impressed the DS can pull GTA as well as it does, I could go as far as to say it's the prettiest 3D DS game I played, and it's got the entire city on it, including the Statue of Happiness...
but I'll definetly pick it up for PSP... I hope they add actual songs to the radio, I don't mind reading dialogue, it's still pretty well written.
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"When Gotham is ashes, you have my permission to die." -BANE