Trickey question, Remember 50% of the sound is the room so if the inwalls work in the room and the regular do not or are not in a good spot they can sound better but in general I have found you can not get better sound from a inwall. The trouble is they are limited by size and by not controling the enclosure the way the wall is built effects the sound.
I see you are using Magnepane for HT, these are not known for good base and smooth sound. Something you want in HT. These speakers are better for vocals and things without alot of bass. Also what are you using for a center?
I would start looking at your center, your sub and the room for main speakers although not ideal the Magnepane should be fine. Remember 70% of the sound in a HT cames form the center speaker.
I see you are using Magnepane for HT, these are not known for good base and smooth sound. Something you want in HT. These speakers are better for vocals and things without alot of bass. Also what are you using for a center?
I would start looking at your center, your sub and the room for main speakers although not ideal the Magnepane should be fine. Remember 70% of the sound in a HT cames form the center speaker.