Yeah, FF13 is definitely worth it but the overall game experience was nothing like FF12 or previous FF games. I haven't actually completed the game yet, I'm midway done. I gave up after I couldn't beat a hard boss battle.
The game has a very narrow path, meaning you can't really explore the different locations in the game like you could in FF12. Once you're towards the end of the game, I heard that the game opens up a little more and you can finally explore things.
The boss battles are HARD. Sometimes I would avoid fighting enemies because I didn't feel like taking the time to fight them but now I realize how bad of a choice that was. So be sure to fight every monster, it really helps to prepare you for boss battles.
So overall, I've enjoyed the game for the most part. I just wish for future FF games, they make them more like FFX, FF7, FFXII, etc.