<font color='#0000FF'>To get the maximum benefit from the Yamaha DSP modes as well as enhanced directionality it is worth it to go for the front L+R effects speakers, by using them, the mains are relieved from effects duty and therefore the sound is quite nice and the effects get their own individual channel instead of mingling with the mains and getting lost in that process.
For two sub setting if they are to be used in the front they have to be of the same size and type, for the rear they can be smaller. My setup includes two Yamaha YST-SW800 in front and one Yamaha YST-SW320 in the rear. I set my rears to LARGE.</font>