Just finished it. I don't think this is a well-known RPG, but I kinda liked the sci-fi theme it sported, so I gave it go.
Not a spectacular or ground-breaking RPG. It's basically the same-old command-driven, turn-based RPG. It took me about 17 indicated hours of playing time to beat it, so not a long RPG. About the only thing that was different than your average DQ-clone was that you could attack by transforming into a beast, which gives you a slightly more powerful attack in exchange for some of your hp.
I did like that you actually had use magic effectively in this game. I really didn't even have bother using much magic for my past couple RPGs, and it makes me wonder why developers even bother putting magic in the game if it isn't going to be a key strategy element in battles.
The game also has some nice, albeit not mind-blowing, cut scenes.
I'd say it's one of the easier Japanese RPGs to pick up and play even if you don't know any Japanese, but obviously, any little bit will help. Just knowing hiragana and katakana can help you which characters can equip what weapons and so forth. Most of the game is pretty linear, and what you need to do next isn't too difficult to figure out most of the times (and downright obvious if you can read Japanese).
The one thing that non-Japanese readers will really miss out on is the humor in the game. Since my Japanese is so-so, I didn't get 100% of it, but I understood enough of it to give me a good laugh here and there. A few of the characters in this game are down right hilarious. It would take quite a bit of the charm off the game if you didn't get these small jokes here and there - it'd be like playing a Working Designs game with all the jokes taken out. But oh well...
In all, I had a good time and I'm glad I played it, but I doubt I'd pick it up again years down the line.
Think I'll try out an English-text RPG next to give my brain a bit of a rest...
[Japanese walk-through for the game
here.]