I brought my NWU parka, 2 NWU trousers, and 2 blouses. I'd only been wearing them a few months after the cutover so they were still pretty good. (Saved me lots of $) If you had gold name tapes / gold USN, you might be able to leave them on, but all rank and warfares must go. I was an E-6, so I took off every patch. You will NOT have any rank or warfare devices sewn on your NWUs the entire time at OCS. The only exception is we took 1 set of NWUs to the tailors near the very end to get our ENS bars and Warfares sewn on, but we obviously couldn't wear them until after graduation.
If you already have the other uniforms such as service khakis, etc, you probably can bring those too. Understand though, that at all times, especially during your inspections, they had better be perfeect (Not even minor stains, tears, etc). They find everything so inspect them well.
In the end, if you don't think they can be made fully inspection ready, I'd leave them at home.
