I posted this question on the Auralic forums asking if people thought Roon sounded better than LDS as I was curious about maybe getting Roon. I would say most people who responded said LDS sounded better. Obviously the functionality isn't as advanced as Roon but that doesn't bother me personally. You will find that thread here:
https://community.auralic.com/t/roon-vs-lightning-ds/936
https://community.auralic.com/t/roon-vs-lightning-ds/936