Items with the "!" in a yellow circle can't be stored in storage, even after the quest has completed. Items I've noticed are Zippy (I'm assuming it's for a later quest after you get 50 kills), the Johnny Silverhand replica clothing, Crash (the revolver you get from River Ward). This remains true even after you upgrade them to Legendary.
Also, upgrading Johnny Silverhands replica gear to Epic, than Rare, doesn't actually consume the original item. I end up with a bunch of gear in my inventory that I can't store.
Also, upgrading Johnny Silverhands replica gear to Epic, than Rare, doesn't actually consume the original item. I end up with a bunch of gear in my inventory that I can't store.