At this point I’ve had all three of those setups, and they are all good in their own special way. My final choice was the DPO, mostly because the immediacy and workflow worked best for me. Ideally I’d have all three, but alas that is too much for one mortal to handle.
I think a DPO in a Shared System is the best of all worlds. I didn’t quite gel with the Shuttle System, but the Furrtthhrrrr was the best part.