I found more of a difference with the height of my surrounds than the flat/angled scenario.

go on...

I found even though the speakers at both high and low positions, were calibrated to the same db level, I could here the surrounds better when they were lower, perhaps it was the softer sounds I could here better/more often when they were lower.

Just above ear level when seated/reclined?

When seated and they are about 2' above ear level.

I use Axiom FMSs with my QS8s and am quite pleased with the results.

I'm about to cut holes in my new audio towers. The ended up up front with my Qs4's as front presence (current back ontop of empty DS cases).
Think I might leave my rear towers in place.
Watched Hotel Transylvania twice in 2 days with the kids.
Subs are setup as good as ever, and the sound coming of the sides of my surrounds works.
Think I'll cut 5-1/4" holes just in case...
Might end up with 4 media towers, I still want QS8's in May.

QS4 on media tower. Sounds no different than it did before.
I'll have a rough hole if we do get the QS8's in May.