What is the best metric to evaluate keyword difficulty?

[nicole.healthline]

Which is better seomoz's keyword difficulty tool or wordtracker's KEI index? Or, do you have another metric you utilize when evaluating a large list of keywords?

[EGOL]

Keyword difficulty numbers don't mean much to me.... however, if I go out to the SERPs and see big brands, government institutions, and other heavyweight sites then I can get some idea of what I am up against.

Also, I take a look at the content that is ranking and if I can create content that is vastly superior then I get a great feeling that I can win.

Who is up there and what is up there make a lot more sense to me than a number.

[nicole.healthline]

That is great advice, but difficult to scale when evaluating thousands of keywords...