Think about the advice the narrator's father gives him about judging people. Do you think Nick, the narrator, judges Gatsby?

I think Nick is, in the end, impressed with Gatsby's skill. Gatsby, like Nick, is an outsider yet able to permeate the filthy rich society of East Egg with his own sense of style. He has a class that the others lack. Gatsby remains an enigma to many and although Nick understands Gatsby's frailties better by the end of the book, he is still in awe of the Gatsby he has built up in his mind:

“They’re a rotten crowd,” I shouted across the lawn. “You’re worth the whole damn bunch put together.”