Let's look at a few numbers ... if your amp delivered equal power to all speakers ... each would get about 23.5 watts. More realistic, IMO, is 0.5Amps (2W) to each QS10 and distributing the rest to the front 3. Then the M80's and VP150 would get about 44.2Watts each. This is about as far as you can crank you system ... and the sound won't be overly great at this level (as we will explore below).

Let's look at the M80's in your system for three cases: 3.5W, 23.5W and 44.2W

M80 SPL = 94db 1W/1m (in room)
1W SPL at 8.5' or 2.58 meters = 94 - 20 log( 2.58 ) or 85.7 db
SPL at w = 85.7 + 10 log( w)
or for:

Code
Continuous Watts    SPL at 8.5'         Loudness Perceived

3.5 W               91.2db              about the loudness of a jazz concert
23.5W               99.5db              disco/night club 3' from the speaker
44.2W               102 db              about the same ... disco/night club 3' from the speaker
Now you’re probably sayin' "Wait a second" 44.2W v.s. 23.5W and it's about the same loudness? Yup, 3db is below most people's threshold to perceive a change in loudness.

Now here's the interesting part ... you're not going to perceive the difference in loudness but you probably perceive more harshness because you don’t have a lot of head room (about 6.5 db) and pulling more current will reduce even that.

On the other side 3.5W is plenty loud at your seat and your pretty safe from clipping. I can see questions coming:
Why? 3.5W seems like so little. Well, 1W is about where most listen to their music ... not loud but a decent level depending on your speakers and taste. 3.5W is a definite increase in loudness although you'd need 10W of power to double the perceived loudness (from 1W) ... i.e. 10x the power doubles the the perceived loudness.

To make maters worse you need 32x the continuous power you set to be fairly safe on clipping. So, 3.5 watts can reach 112W peaks. 10 watts 320W peeks. And ... that's one speaker .... Now start adding on more and you can see why some go nutzoid on power. Have fun.