Looks pretty neat. The only thing I see going against it is that you need 4 ethernet (well one for each remote device) all the way to the HDanywhere and all your sources (which have to be in the same place - not a big deal since that'd be common). i.e. you can't put it in a server cupboard under the stairs or something like that unless that's where you keep all your sources.

I presume that's OK with you?

Edit: I'm guessing they're kinda expensive too?