I try to only post Contests from reputable companies(as I think the other DISers do also) some websites list all contests and some may not be all above board, ie just wanting your name and email addy and address etc for some kind of scam or list.
Just a word of caution. I have not checked out this site so I am just talking in general terms.
I make it a habit of only entering contests that I recognize the companies supporting it. Just to be on the safe side.
But thanks for the link I am going to check it out.