Xenosaga episode 1 is the only one I played, and it was soooooo boring. I never finished it.
Suikoden 3 seemed pretty good - I got about ten hours into it. The writing was good, and the gimmick of switching between main characters was cool. What ultimately made me stop playing it was that combat was too hands-off for me, and it felt frustrating as a result.
You had six party members, but instead of controlling all six, you would group two together and they would pool their abilities and spells and stuff. This alone isn’t so bad - after all, I’m enjoying The Last Remnant, which I just realized is strikingly similar. The difference, though, is that in Suikoden 3, this causes problems that get you killed. For example, one of your pairs casts an AoE spell (many of which target indiscriminately), your other character will attack. So, this means that at least ONE of your characters is going to walk in and get hit by the AoE spell, and probably die. Now, imagine if you casted a spell with your other two groups - two more people would be hit by it. NOW, imagine if your other two groups both did melee attacks…you get the idea. I don’t like being punished for something like that.
It sucked, cos I was really interested in the story, but GOD that was such a frustrating mechanic to have to work around, that I eventually gave it away to 984, who accidentally jacked his copy up.