Can I outrank large sites?

[frank]

We have found a keyword which has very good demand. Now after doing some researching we have find that the first page is mostly filled with large sites (more or less like CNN or BBC), but there are also two or three low quality sites. I can assure you that I build content alteast 5 times better for that keyword than all of them. Should I go for it?

Publish the article anyway. If you can produce a good article comparing to your competitors then you should do it.