A wonderful collaboration of two series, with charming gameplay and 400+ hours of play if you really get into it.
Everything else about this game just seems wonderful to me. One very good thing is that this game can be played absolutely at any speed you want to. The game has features to run through dungeons very quickly, but it will always let you stop and think things out, and believe me, by the time you save the world you will have had some scenarios come up where you'll want to think out the best course of action.
By the time you save the world in this game you will have played 25 hours and will have witnessed one of the most charming stories in any video game. But the game hasn't even hit its stride yet. I only play extras after the story is finished in games if I really like the game and feel compelled to, and oh yeah I wanted to see what this game had to offer! Many of the game's features don't even appear until after the storyline is complete. Don't misunderstand, saying "the storyline is complete" in fact is not true, because really nice scenes long after the storyline resolve things that never really finish in the main storyline (the first 25 hours).
Once you've played 80 or 90 hours your heroes will be extremely strong, and none of the ordinary dungeons will be any challenge for you. BUT, this game includes two wonderful features (neither of them making any logical sense but that's alright) that will keep the challenge up even after that. The first is missions where you have to escort a weak pokemon deep into a dungeon. If your client gets beaten it is just as bad for your team as if your heroes are beaten. The bigger and better challenge-increasing feature is the three dungeons where your characters lose all their advantages (level and special abilities) every time they enter. Don't worry, they'll get all their levels back after they leave the dungeon. These "level 1 dungeons" are a really special challenge the likes of which I have only seen in Lufia games.
And I haven't even mentioned some of this game's coolest features. If you know someone else with the game, or have internet access, you can have your defeated team saved by someone else and have another chance at the dungeon. That feature's so neat I hope other games pick up on it and add it to their series. And hey, this is a Pokemon game, with - get this - 413 varieties of pokemon that can join your cause! Well, 28 of those are different Unowns so there are really only 386 recruitable species, but still it's impressive. After completing the story you can return to earlier dungeons with tough legendary-pokemon bosses like Zapdos and recruit them. And some of the non-legendary pokemon, like Chansey, are even harder to recruit than the legendaries. Another neat feature is that it IS possible to steal items from shops in the game, but you REALLY have to know what you're doing not to be beaten (without the chance to even be rescued). If you're dedicated and lucky enough to recruit the shopkeeper, you'll have a decided advantage in those level 1 dungeons I mentioned before.
If you only play till the end of the main story, this game has 25 hours of gameplay. But I think it's a safe bet you'll want to play more than that. If you play long enough to complete all the dungeons it'll take a little over 100 hours. That's pretty good for an RPG, BUT, if you really like this game and want to recruit every single pokemon, and want to get into the internet friend-rescuing scene, this game has 400 hours of play!!! That's amazing. I've logged 425 hours, and I still want to play more. And the graphics only bothered me about the first one-fourth of an hour.