You're asking the wrong question.

The question should be do you prefer canon or nikon lenses, depending upon the type of photography that you do, or see yourself doing.

You'll wind up upgrading the bodies every so often, but your glass you'll keep for a very long time.

That being said, I'm partial to Canon L series lenses.

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You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist.