Which URL is better?

I like the top one. I don't like having to look down to type the dash in order to type in a domain.

I think you will get more traffic from the one without the dashes.

 

Shulz is correct, Google will soon be accepting the underscore (_) character as a keyword delimiter. However, i think this is for underscores only, and not for dashes so this would not help you in the case of your domain.

Furthermore, I think you will lose a lot of type-in traffic because people will forget about the '-'s

In short, go with the first domain.

 

Google has accepted the dash as a keyword delimiter for a long time now (as far as I can recall). I know the other major search engines do, as well as accepting the underscore character as well.

For once Google's just playing "catch up".

(Oh, and about losing traffic for not typing in the dashes, that's what registering both domains and 301ing one to the other is for.)

 

Use the one with the dashes and have the one without redirect.

 

Number 2

martial-arts-fighter.com would be better because the hyphen (-) is interpeted as a space by Google.

But don't use 3 or more hyphens, Google doesn't like it.