The only concern I would have is when you are driving 4 or 5 speakers with the 1050, there is some possibility of the combined load of those 4 or 5 speakers stressing the power supply.
This would depend on:
1) what mode you are using to determine the signal of the additional (from stereo) channels - for example, if you are running multi-channel stereo, there is a good chance that all channels would see demand peaks at the same time; where as most movies will not (an explosion to the front-left will arrive at each of the speakers with different timing). So worst case is your maximum peaks are occurring on all speakers at exactly the same time.
2) what is the impedance and sensitivity of the other speakers. If you are running Gene's Status Acoustics 8T's as your surrounds (which are power hungry and drop below 3 ohms), you are overloading your amp before even adding in the mains!
I suspect you are fine as you are, but we can't rule out the possibility that your system might tax the AVR without knowing this.
One test you could perform is to listen as loud as you ever would to the 4/5 speakers, then switch to stereo and listen to see if it sound cleaner of not. I feel very comfortable that your AVR would handle 2 BMR's by themselves without issue, so that can be a reference.