Hi Mp
How big is your room and what are the distances and relative positions of the speakers positions from your main seating position?
I experimented with 7.1 in a small room where the rears were only a couple of feet behind the couch. I took them out as I did not find a noticeable improvement vs. the inconvenience of where they were located in a walking path.
Alternatively, I now use them in a much longer room with a lot more space between the rears and the seats and I am now more happy with the results. Adding rears is still not as breathtaking a jump as when you first add the 5.1 side surrounds but it is an improvement. I suspect that adding height and width will be similar. It won't be a huge leap like that first step into surround sound, but it could add an improvement.
I have no experience with height or width speakers but thought I'd add the relevance of distance to the rear conversation.
