Likely gonna have to do some testing to decide on that one. Especially considering both tier gloves and chest have absolutely garbage stats on them. (spirit/mastery and crit/mastery). Just offhand I would have to say its likely not worth on it aside from a few select fights.
I actually meant the item level of the tier pieces, you mentioned the non-tier was heroic 2/2, I'll include both scenarios below though:
If you are swapping those out for Heroic Tier (535), then definitely - should be at least a 5-6k dps increase.
If you are swapping those out for Normal Tier (522), it's still worthwhile actually now that the set bonus works. About ~2k dps increase without upgrading the 522's, about ~3k5-4k if you made them 528's (522 2/2's).
Now that the set bonus works, it's pretty valuable!