I'm not driving my M3TS with a receiver (separates), but they do pull double duty in our living room connected in a 2.2 setup.
While the M3 is the best sounding music speaker I've had in my home, I feel that due to the "directivity" of the design there are better speakers for home theater use.
The sweet spot (in my room, in my system) is fairly small. This is fine if I'm sitting in it listening to music. But, if I have several people watching a movie spread across the room, most will be out of the sweet spot. I hear changes in sounds across the two speakers if effects are dramatic (a plane flying across the screen), but dialog and quieter passages sound like it's coming from the speaker I'm sitting closest to. (Kind of mono).
That said, my M3s aren't going anywhere. I absolutely love them for music. If your needs are directed more at HT, there might be better options.
One speaker I owned that worked well for casting a huge sweet spot (in a 2.2 setup) was the Gemme Audio Tanto 2 (now defunct Canadian outfit). Simple drivers with no crossover, beautiful transmission line cabinet, small (high WAF). They don't produce the bass of the M3, but I really wish I had kept them to rotate in from time to time.