hi deo!
while it is true that the sound that normally comes out of your side surround speaker is very minimal over-all compared to that coming out from your center, fronts and subs, it is the whole equation of where it all emanates from which count. imaging from almost all angles is equally important to provide cinematic experience.
i haven't tested wharfs and only heard my M7Ds and a pair of Definitive Technology. my take is go for dipole for side surround:
1. go for high sensitivity and, no less than 100w per channel at that,
2. low freq specs would provide crispier sound,
3. the dipoles provide better imaging
all this IMHO.
hope this helps your quest.
cheers!