The downside to the HDMI Detective is it's limited in what resolutions and audio formats it supports. If you're fine with the limited subset then it might be OK. But for $100 *per device* that's a bit expensive. From what I gather I'd have to put one on each source output, before it goes into the matrix switch. This would let the source devices all think they're still talking to the same output device. This, apparently, is important when it comes to avoiding audio output limitations. As in, you get stuck using only stereo output because that's the lowest common denominator across all your TVs. So your home theater projection TV and receiver wouldn't be able to use 7.1 surround (or the like) because there's a low-end TV in the office that only accepts stereo.
I think there's a little more planning required here. I'll have to look into this audio limiting issue more. I don't feed multiple TVs yet but will after we remodel. So I'll have the option to order whatever TVs are 'most compatible' with the whole system. Or, as some people are doing, use an AVR in places where the TV display alone wouldn't do a good enough job. Perhaps only using it as a way to 'downgrade' from the distributed HDMI signal to whatever the lower-end TV supported.