Gates to Infinity: Definitely the Worst in the Series, it's Not a "Bad" game. But it's not Amazing
Ouch! Not having played many of the others I can't really refute that. It is fun to play, though.
You left out some of the technical details which were what actually drew me to this series. For instance, the entire Mystery Dungeon series is Rogue-like in their use of randomized dungeons, multiple floors, with difficulty of the floor being scaled up the further you go. (Some feature perma-death or death related penalties, but this one doesn't, or they were really minor, I forget). I stumbled over the Pokemon Mystery Dungeon stuff because I had been playing Mystery Dungeon: Shiren the Wanderer and really needed a new Rogue-like to play because here I was using my New 3DS to play an ancient DS game. They are also largely single player. You can "summon help", but you're pretty much on your own. There's also a sort of limited multiplayer mode for some of them, but I never had a chance to try it out.
Super Mystery Dungeon: The best one in my Opinion.
I skipped Super Mystery Dungeon because it dropped the customization that I liked in Gates to Infinity, ironically, I dropped it for features having nothing to do with the Rogue-like genre that brought me to Gates to Infinity to begin with. Once I beat Gates to Infinity, the only thing keeping me playing was that I hadn't unlocked all of the areas for customization. So I would do more dungeon runs, get more pieces, and unlock more areas for development. But then I managed to get them all, and there didn't seem to be anything left to do.
Out of curiosity, why do you capitalize words seemingly at random? It makes the article harder for me to read, but that's probably just because I'm slow. You don't need to change it or anything, I'm just curious why it is you do it.
RE: Thoughts on Pokemon Mystery Dungeon