I picked it up based on the fact that 1) it was a Tri-Ace game and 2) I saw it in store for ~$20.
I still prefer Star Ocean 3, actually, but RS is a good time. The mood is a lot lighter than SO3 (and the game can be funny as hell, especially earlier on), the battle system is less complex, and the story isn't quite as interesting (hey, I enjoyed SO3's plot...just not its presentation). Suprisingly, RS's presentation is far and away the best Tri-Ace have ever done. SO3 had so many akward moments of characters just standing there talking. RS never has that problem and all of the cutscenes are very enjoyable to watch.
The battle system is kinda disappointing. Fun, but too simple. For one thing, you are stuck with Jack. Nobody else can be controlled. You have your basic attack, guard, and timing based parry. You also have something called the volty meter, which charges up as you do normal attacks. You can unleash these attacks using square (either alone or as part of a combo). Defeating enemies gives you "chain" points which you can basically allocate towards your weapons and open up new combo possibilities.
The game also decided to use time. There is always a clock ticking (and that obviously means day/night cycles). NPCs actually go about their business here based on the clock and seem more active (rather than everyone always standing around). There are a ton of chraracters to recruit as well (kinda like Chrono Cross) and time plays a big role in that. You'll be able to get new missions from characters depending on the time of the day and such as well.
The dungeons and overworld are nowhere near as good as SO3, though. It is beautiful, no doubt, but rather different (more like the locales in something such as a Tales of game).
The visuals are quite stunning, actually. Very cool designs at 480p 16:9. Everything is 60 fps EXCEPT the battles...which only run at 30 fps (annoying). Not a big deal, though, I suppose. The sound is good. Music is by Iwadare and it has that bouncy Grandia sound to it. Though, I MUCH MUCH MUCH preferred SO3's soundtrack (one of my favorites). I love Iwadare, though, but this isn't his best work (good, but not great). The voice acting is absolutely excellent, though. In fact, Jack is voiced by the same woman responsible for Naruto's voice (which is fitting, considering how Naruto-like he is).