Welcome, the helpfulness of Axiom’s staff and the minimal amount of sniping by members of this forum also convinced me Axiom was going to be a quality product. I also think you’ll be fine with the Denon 3808CI, since my Denon 2807 plays more than loud enough.
Since your going to be sitting so close to your QS8s I also suggest you mount them up around 6-7 feet. Having them to close to your ears might make them sound more directional and less enveloping. You could try moving them lower later if your new room allows.
Your center should sound fine either way. A couple things you might think about. If you’re sitting very close to the front make sure if you put it below that you don’t have anything blocking it like a coffee table or your feet if reclining. Also, the closer you sit the more important I think it becomes to get the VP150 near the same level as the tweeters on the M80s. Not critical but does help them blend better.
