I give this game an 8.5/10.
Be warned, this game will not be for everyone. It is still in Early Access, so a there are missing features, bugs and glitches (but that's to be expected). If these things strike a nerve, wait until the full game is released. Most of the glitches and bugs are easily avoided though; just use the F5 (quicksave key) often. Then when something does go wrong, you can automagically timewarp back and do it all again :)
How I would sum up the world: Think Tatooine landscape filled with sword-wielding samurai and ninjas. No magic, no fantasy. It feels like it could be real (assuming it's on another planet :P).
I love this game because of the grind. Sure, you have to sink in a lot of hours to get anywhere, but nothing matches the feeling of sheer satisfaction when you've built up a strong party, a well defended base and little stands in your way as a threat. The game was tough to learn, so you'll need to lean on the wiki for support for the first few hours at least. But once you've found your way it's all smooth sailing.
My only real dislikes about the game are the bugs. The one that annoyed me the most was the teleporting 'dead' bandits. Watch out for these bad boys because despite being 'dead', they will teleport closer and closer to your storage buildings then loot your stuff. And no matter how many times you go to loot the stuff back off them, they will always win. F5 is the only way to save the day.
Yet some of the bugs are more amusing than annoying... Like men sleeping like bats, hanging upside down off the sides of beds. Or shopkeepers within shopkeepers so they look like they have two faces, four eyes, two noses and four ears :P
All in all, if you like games that require a grind and can put up with weird stuff happening, dive right on in. It's worth more than you pay for it. If you like a grind but don't like glitches or blank buttons, wait for the full release. And if you don't like a grind, then this game is definitely not for you.