The HIW-1's do not have an enclosure, so their sound and performance is greatly influenced by the wall you put them on. They do have the same drivers as the HB-1 Mk2's. It terms of SQ, it ultimately depends on how you set them up, but with the natural inability to toe in the speaker, you do get less highs if you sit off axis and without a ported enclosure the HIW-1 will not be as efficient in the low end so you tend to lose a bit there as well. So in our demo room, if we use the HIW-1's as mains flat against the front wall, then my experience has been that tends to be a bit more mid-centric. However, when used as a surround, the differences become significantly less noticeable. Each room is different though. Right now, we're working through design issues with the CCB-8 in-wall variant.