AMR CD-77 vs. Ayon CD-5 as DAC/USB & CD5 preamp

Do any of you have any experience with either the AMR CD-77 or the Ayon CD-5 as DACs via the USB port you can share?

Direct comparison would be fantastic, but individual descriptions would also be definitely helpful.

Also any experiences with the preamp section of the CD5 would be appreciated.

Thanks and enjoy the tunes,
Art