Ayre QB9 Dac . Upgrade to the new QB20. Vs competition In the $4-5k range or less

Hello I am looking to find out regarding the New Ayre upgrade for All QB9 dacs to the New QB20 Dac 
i see 1 review and  reviews many times are in part swayed with $$.
how good is this new upgrade ,and how would the QB20  and Schitt Yggsdrusil stack up 
and compare with each other . For these are my 2 options , please do chime in ,Thanks much.
I have been told by someone that I trust that the Twenty version of the QB-9 is as good as the QX-5.. he owns both.  I am due to have mine upgraded in about 2 weeks and will report back.
I got the upgraded QB 9's, but have yet to install them.
I own the Ayre Codex, and the Schiit Yggy and Gungnir were just about the same with regards to sound reproduction. With the Yggy coming a close second.
I only bought the QB-9's due to Ayre saying the Twenty upgrade were a significant upgrade. (My Codex was sent in for repair, at the time).
Thanks for reminding me to hook the QB-9 up.😀
sorry for a minor threadjack, but i have a quick question...

the qb9 is USB input only, yes?  i have a codex, really like it... but i don't use usb as input (have streamer not computer doing the streaming)... would like to hear ayre's evolution of their DAC's but i can't use the qb9 (upgraded or not) if it is USB digital input only...