Sure, but it's not like it is some hack cheat/exploit and yet I see people calling it that (not here but on other forums). When I did it with the Queen's Wrath I wasn't even aware I was doing something "different" until near the end. I just thought if you did the bounties quickly for some reason they popped up again. I didn't question it
.
I have the radiant exchange available now I think - isn't it just Rank 3? I think the only things I'm still locked out of are the second class items and the last shader. So Rank 4 is really just optional for dress-up like it was for Queen's Wrath. I was one bounty away from rank 3 in Queen's Wrath. I would have liked getting the unique items from that. I see very few people with the shader (I'm talking Prism Dancer not the Rosegold) and ship from that. In fact, I've only ever seen one person with the ship. And I've never seen the shader that I'm aware of. That was before they had preview available on shaders and I was always curious what it looked like.
As for Eris, the Warlock rank 4 class item, at least, isn't all that interesting. I prefer the one I have now (from Rank 2). I also have the Hunter rank 2 item. Note that you can just buy all the items with one character and just swap them via the Vault. My Hunter is barely rank 1. So there's really no point doing Eris stuff for more than one. I did some on my Hunter last night just for the variety (as I had two Hunter-specific ones) and general XP (for my one piece of Raid gear). At least they provide some variety from the endlessly repeating Vanguard bounties. Those are starting to bore me to tears.