@TLS Guy thanks. The room is unfortunately what it is.
I'm assuming your "do more harm than good" has nothing to do with wired or not? Is the issue that I cannot get them far enough behind the listener?
As to the front speakers are you just speaking of bigger, did you know something bad about those in particular?
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Well, I got the unit. The good news is the latency in a brief test with a scope was 16.4ms, well within the ability to correct. I did some experimenting with the output from an ESP32 and the DAC inside PC, and both could not produce a clean sine wave even, so I did not bother trying to do any kind of distortion analysis (and I have nothing at all in the audio realm, just stuff for debugging regular digital electronics).
The mediocre news is I can't manage to get it to pair at 5.6ghz, only 5.2ghz, though that may not be much issue.
The really bad news is that I had mis-read my receiver's manual. It covered two variants, and the variant I have has no pre-amp output. So I'm taking already amplified signals as input, which the device can do, but is an awful approach. I have an unamplified zone 2 out, but it can't be adjusted to be specific channels, only a stereo out.
I'm going to go ahead and hook it up the "bad" way and see what happens.