Each persons work is unique, these two guys have great talent and a strong set of skills in software that makes their art appear a breed apart. However each piece they do takes months, sometimes even more. How long do most others spend on a particular piece?
I was amazed at how long PMD (Phil McDarby) takes on his work.
http://www.renderosity.com/mod/gallery/browse.php?user_id=19080

Try planning out a project that is bigger than anything you've ever done before, see where that goes.

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Ockham's razor- It's that simple