I prefer a large radiation area and front firing, tall horn or horn hybrid design with a controlled, narrow and fairly uniform dispersion pattern. Smaller and lower horn-based designs tend to be too "beamy" and upfront sounding for my taste and more easily give off themselves as speakers than a more uninhibited field of sound.
Multi directional speakers can have an advantage with a more spacious soundstage, but generally I find them too diffuse sounding - indeed almost too or even annoyingly spacious (in which case they mayn’t have been well implemented).
A front firing only, tall and large radiation area horn-based design as described above to my ears compensates immersively through the sheer size of its radiation field with a more distinct, yet still relaxed and fuller presentation - a good, a rather natural sounding compromise, I find.
@audiokinesis wrote:
[...] note that (unlike your main speakers) it is the POWER RESPONSE of the dedicated-to-reflections speakers that matters most.
Why isn’t the power response of the main speakers of a primary concern here? Introducing a reflective sound field "actively" with additional speakers is also an additional measure to get right. Isn’t that a degree of complexity that can invite more problems than what it tries to solve?