Ifi Zen Stream vs Lumin U1 mini, worth the jump?

I’m trying to get a good streaming setup going again. I have had lumins in the past (D2 and T2) that I really enjoyed but ended up having to sell the T2 awhile back. Anyways I’m on the hunt again and wondering if it’s worth it sound quality wise and usability wis to jump up from something like the Zen stream to a Lumin U1 mini used or on sale now that U2 was released. I haven’t decided on a dac yet but most likely something r2r like a Pontus II or similar. 
i do like the leedh volume control on the lumins as I have a croft Phono Integrated powering my Harbeths which has no remote, but that’s not a deal breaker. Just wondering if anyone has insight on any sound quality differences ?