If a keyword is in the domain name and the doiain has a PR of 4 or 5. Dont you think that they are hard to compete with? Thats what happens with most of the highest paying keyword. There are monsters in the internet and SEO world. We are just a little bees here. you would be the luckiest person on the planet if you find a highest paying keyword with lowest competion. That's why I believe on this thing that we should just focus on quality and keep in mind the CPC also. But we should not solely go for CPC only. Just sayin...