I'd mount the Aerial 5s on the wall to the side of your listening position. In my experience it is important for the mid and HF to be similar to the LR mains, especially for music recorded in DTS.
After some experimenting, I use a pair of KEF Reference 102s mounted on the wall as surrounds for my Reference 107/2 mains. It adds a nice depth to the sound stage with DTS and many SACDs. The newer KEFs with Uni-Q just didn't sound right. I no longer use a center channel, and rarely turn on the amp for the rear channels, so I mostly use 4.1, or is it 4.2 with 2 subs.
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After some experimenting, I use a pair of KEF Reference 102s mounted on the wall as surrounds for my Reference 107/2 mains. It adds a nice depth to the sound stage with DTS and many SACDs. The newer KEFs with Uni-Q just didn't sound right. I no longer use a center channel, and rarely turn on the amp for the rear channels, so I mostly use 4.1, or is it 4.2 with 2 subs.
db