Hi,
I'm a little confused by what you mean "positioned cross-wise" but in any eccentric set-ups, I always prefer multi-pole radiating surrounds because they are much easier to locate (even at different heights and distances) yet they still supply excellent immersion in the soundfield without losing rear-channel directional cues in 5.1 operation. I think the same would apply for 6.1 operation.

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)