Default First ROM

So I just found out about creating a rom slot and I am wondering a few things. Once I make the slot I'm assuming that I need to install a rom on it in order for it to work. Can some one please recommend the best rom available for the note 3 and maybe some tips for a time flasher. Also will I be able to install cwm without tripping Knox on the new rom? Please respond quickly if love to do this tonight.

Thanks!

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