Which domain is better in your opinion and why?

Why do you asking about it?

Because one domain should be promoted not both it is connected with SEO.

I think you can use redirect 301.

yes I can but when I make link exchange I need to decide what url should look like and google looks at it.

I think, that mytibia.eu... becouse is easy to remember and looks better for me.

http://www.mytibia.eu i liked everyone use this www

Not everyone uses it. It really depends on point of view. For example mytibia.eu is shorter than http://www.mytibia.eu

My vote goes for: mytibia.eu

http://www.mytibia.eu <- I'm a lil lazy to write it hehe

I never write "www" when entering any page anymore. So my vote goes naturally to mytibia.eu