I think you should get it if you want to. It's a considered a bad game by dieheard fans of the original game but if you love Symphonia, there's enough carry over from before if, like me, you just have to see where your favourite character ends up after Symphonia's endgame.
It IS a horrible game. The only redeeming factor is seeing my favorite characters again. Including Robin Irving, except he isn't anymore because the VAs changed.
Let me list the pros and cons...
Pros:
-Nostalgia Factor
-See the aftermath of the last story
-Have more ToS to play.
Cons:
-No open world travel. Excluded completely.
-Universal control is only for 2 characters, and whatever pokem--er, I mean, monsters you capture. All the old characters you can not control, don't level, are unable to switch equipment, etc.
-Characters are annoying and forgettable. I completely forgot the protagonist's names, but I remember all of the old cast's names fine.
-Story has been knocked down multiple notches. It is nothing compared to the glory that is the original ToS's story.
-The game is short. Short as hell. It's about 1/4 the length of the first one, likely less.
-Clunky controls.
-Different VAs
-And more...
Yeah, you decide.