Trust me, skip ES. It's awful. That's how I feel. I wanted to like it. It is not representative AT ALL of Vesperia. I thought it was an insult to me, as a fan of the genre, quite frankly. If ES was my first JRPG, I'd hate them all.
As for judging a jrpg by a demo, that's silly. If you've never played Vesperia, or Abyss, or Symphonia, then A. You've missed out on great games, and B. You don't know what you're talking about, and you've just conjured up some way to marginalize the games in your head. The demo isn't indicative of the game, and Eternal Sonata is on an entirely different wavelength than Vesperia, especially in the battle systems.
If you want to spend 20 bucks to find out what ToV is like, then buy Tales of Symphonia or Tales of the Abyss. Especially if your younger and just being introduced to jrpgs. It's like a less in depth version of Vesperia, which is without a doubt the best jrpg released on a home console this generation besides arguably FES, I don't care what your tastes are like.
You can do what I suggest, and enjoy yourself, or do something different, and screw yourself over. That's just how it is.
If you hate Anime, hate jrpgs, and hate any game that has been released in the last 2 years, odds are you'll STILL probably like Vesperia. Ask anybody who ever played it.
IMHO.
In fact, if you wanted me to recommend a jrpg on this generation of consoles, I wouldn't be able to do it, if Vesperia exists. However, don't take that to mean that standards have been lowered because Vesperia exists. I would also rank Vesperia as the 3rd best jrpg on the Playstation 2, were it on that console, above Abyss, FES, Symphonia, and a slew of other games. I can give you my full PS3 jrpg ranking list, if you request it. This isn't something I've just made up. I've thought it over previously and made an encompassing list of how I would rank every PS3 jrpg I've played, from FFXII, to Growlanser Generations. Vesperia marks very highly on that list, and it ranks in the top 20 jrpgs that I've ever played on any console.
Saying that it's "good for a new jrpg" is a gross understatment. It's the best Tales game I've played, and it's the best Tales game yet released, imho. I'm not the only one who shares that opinion, either. Go check out some user reviews and surf the forums over at Gamefaqs. See what the fans think about it. It's already a cult classic. The casual core gamers just don't know it yet.
Eternal Sonata is generic jrpg lite. I know that sounds trollish and arrogant, but good lord you have no idea the ire that game truely built up in me after how much I'd hyped myself up for it. It has no character development, and no depth in its battle system. Its such a joke to compare it to ToV, which is on the opposite end of the spectrum, where it's actually a little too complicated. ToV's endgame on playthrough 1 took me longer to complete than me beating ES twice. Me giving that game a review would not be nice.