I've heard great thinks about IDJ and wanted to go with them, but they said upgrade policy is really only on studs. what do you think, just go with them or is there somewhere as good in NYC (I am a train ride away so want to see the ring I purchase, not buy online).
Good Old Gold and Diamonds By Lauren would be my two recommendations for vendors around the NYC area based off reviews I’ve seen here on PS. And I’m not even based in the USA!
Regarding Brilliantly Engaged, I remember there was a PSer who had an issue with BE honoring the upgrade policy. Turns out their upgrade policy had a clause which states it's subject to vendor's latest upgrade policy (which was different from their earlier upgrade policy) - so the PSer was out of luck. There's a thread on here somewhere.
If you are thinking of upgrading, whichever vendor you end up working with please get all the upgrade policies in writing on the receipt so that it's very clear what you are agreeing to.