Just beat the demo, you do have to play all the way through to get all the unlockable items, though just starting the demo gets you some of them.
Everyone has different tastes, I'm certain there will be a ton of people that'll love this game. Amalur has nothing in common with Skyrim, and I think I went in with somewhat unrealistic expectations as a result. Amalur feels VERY much like an MMO, and I've never been fond of that style of game. I think the furthest I ever stuck with one was getting a charcter to level 7 in DC Universe. In Amalur walk around and the enemies are standing around waiting for you to kill them. You look for the red dots on your minimap and you rinse and repeat.
Fortunately, the combat is a ton of fun and I can only imagine it gets better with the later combo's you'll inevitably unlock. Again, I think a lot of people will like this. I liked going quickly between bow and dagger, though I'm not a huge fan of how the shield magically appears out of nowhere when you block. The combat is fun and God of War'ish.
The graphics are middling at best however, they're nice enough but feel like something of a cross between SWTOR and Warcraft 3. Lots of nice colors and the animations are pretty slick which I definitely appreciate. The demo has some irritating bugs like NPC's that don't move their mouths during dialogue.
Speaking of the NPC's, I started skipping all the dialogue pretty early on. Before I had even reached "mad scientist guy" I had begun hitting the "X" button frequently (360 pad). Typically, I never skip dialogue in games so this isn't a good sign. This game also has mouse acceleration issues, the mouse moves too fast in combat but way too slow in the menu's. 360 pad fixes that.
The menu's are pretty dreadful, it's just menu's buried in menu's. Making it worse is that this game appears to be a trash loot bonanza. You're constantly picking up random loot which didn't apply to my chosen character build (bow/dagger). Reminiscent of Mass Effect 1's loot system in some ways. Since I was using a 360 pad I didn't see an easy way to get straight to my armor or weapons selection screens. Maybe there's a shortcut on the keyboard...
I definitely went into this demo with misguided expectations. Open world... to me that means Elder Scrolls, GTA, or even something like Assassins Creed. The maps/levels/areas in Amalur, or at least in the demo, feel very closed and uninteractive. Movement is restricted, there's no leaping off any ledge you see... you're blocked from doing stuff like that. Everything's also bolted down, you can smash crates but there's no fusrodah'ing a table and watching the stuff go flying. There's also no jumping in Amalur, you run or roll but you do not jump.
I actually considered this game a must buy heading into the demo, but it's now a "wait and see". Many people will probably love it, though. It's definitely a quality title if you're into that MMO-styled "there's the enemies standing in a field waiting for me to slay them" system.