I'm sorry, I was getting back to the original question. I meant for the surrounds- the columns on the sides. I have the cabinet mounted speakers already for up front, they work great.
Because of how close the columns are to the seating area, especially your left one, the QS8's really will perform better than bookshelf speakers.
I tested both in just such a scenario and it wasn't much of a contest. You can always get M2/3's and test for yourself, and then use them for the back, but with your layout you'll get the best surround sound from QS8's all around. Whether or not that is worth the extra $ is up to you, but once I heard QS8's all around in my room there was no going back.
