Solid 7/10. I think it would have been a 8/10 if it ended after Luca Blight was defeated, but all that stuff afterwards just seemed unnecessary. I would have liked to see some more backstory regarding Luca and what made him go nuts in the first place. I know we get minor details on it, but I just wanted more.
With this, I've finished 4/5 main Suikoden games. The only one I have left to finish is 4, which I'm forced to play through from the start as I got halfway through and then took a break, only to forget where I had to go afterwards, so I stopped playing.
So far, my rankings of the 5 games are as follows: S5>S3>S2=S1>S4. S3 gets a bit of a tip due to my personal history with the game. But 5 is still my favourite of the series.