I have run the MG1.6 with 600 watts, and that's just for the 80 Hz (or so) up left over after the subwoofer. No problem. In terms of voltage (which is what the speaker responds to) 1000 watts is not much different from 600.
I made some measurements to see if I could get by with a smaller amp, and concluded that, surprisingly, 600 watts was not overkill. However, for monoblock convenience, I am now getting by with a mere 350, which my measurments showed would cover all but absurd volume levels.