What about vibration between amp and speaker? It's a little hard to keep the vibration out of the amp when it's in the speaker cabinet. Then you have to run power cables to the speakers. maybe not as much an issues if you are already using mono blocks next to your speakers.
I think there intended use in inexpensive home studio's in the near-field where you will not be listening to them an any level that will severely interfere with the amp.
Powered sub woofers have gained some acceptance so we will see what powered speakers does in the future.
I have no interest in them, if that's of any use to you.