Sky Odyssey is decent. I own both games btw.
I suppose you will have been put off by the two comments above for getting Sky Odyssey but here are pros and cons.
GGB - Pros
Mostly a really fun game.
The missions are deverse and will have you coming back to play them a few times.
GGB - Cons
Too short basically, only 6 missions so you will want to put it onto the hell mode before playing.
Basic graphics but they do the job.
SO - Pros
A original game, theres nothing like it on the PS2 at the moment.
A really fun game reguardless if a few people think its boring, you won\'t apprechate the game from a demo or a short play, its a sit down with it and do the training missions, have a few flights kind of game before enjoying.
Tons of replayablity.
Each mission is different and very fun.
SO - Cons
Really there are no cons to this game other than the lack of any decent plot, but it doesn\'t take anything away.
A touch of slowdown on a couple of missions but it isn\'t bad.
Overall its a shame to overlook Sky Odyssey cause it is a very good game, although I can see you getting Gun Griffon Blaze now because of a few comments, thats fair enough though, they are both really good.
So go with Gun Griffon Blaze incase you may not like Sky Odyssey, but if you like Sky Odyssey you will prefer it over GGB, its really good. They both are, you can\'t lose.