Well, I'm pretty sure you would be able to tell pretty quickly if the video suffered.
Personally, I would run everything through your Lyngdorf and keep it simple. I've also never seen an Audio Return Channel that was all that reliable.
eARC when using Roku
I have a Lyngdorf mp 60 2.1 that is currently connected to a Roku ultra via HDMI for both audio and video. Is there any advantage connecting The Roku directly to the tv, a LG 2.1 hdmi, via HDMI and running the audio back to the Lyngdorf from the tv using the eARC HDMI of the LG tv. Since the video from the Roku is not processed and is only passed through, by the Lyngdorf a direct connection to the tv for video maybe better? Please advise. Thanks.
Guy