Ayon S-10 or L509x

Any insight on actual use and sound of the Ayon S-10. I was looking for a tube pre and streaming and came across this unit. I searched the forums and found much info on S-3/5 and amps. Ayon seems to generate the love/hate emotions and not much in between. The idea of the PCM to DSD conversion with tubes sounds compelling. 
Option #2 - I have an opportunity to purchase a Luxman L-509x at a fantastic price but that would be sending me into another direction.
Currently have Parasound A21, ATC SCM19's, and using Cary AiOS as pre/streamer.
I looking to make my system more musical/warmer with out softening it too much. I can not afford to change up everything. 
So do I add tube-pre/streamer to A21 or replace A21 with 509x. Feed the 509x with the Cary until I can replace it.