I have twin boys arriving soon
Congrats and good luck! Mine's 9 months now, the thought of having twins makes my nervous twitch flare up.
Logitech harmony 600
I see you do have a Harmony, so keep the Sony for now and wire all the HDMI's to your TV. You can then use the Harmony's macro capability to switch the amp and the TV at the same time, if you not doing so already. You'll have exactly the same experience as getting an HDMI amp and routing it through the amp, less the HD codecs. I say again,
you'll be unhappy with that Yammie after you've had the Sony for so long. Coming from Prophecy I know you a gear slut, but do resist the temptation. Take it from someone who's gone down this road already...