As always this will depend on room size and playback levels, but...
I used the A'diva as rear speakers a while back. It was a large room and SPLs got big on occasion. They never complained or sounded overworked. Personally, I'd tend to disagree on spending more for rear speakers, unless you really do need more max output capability (or prefer the aesthetics). I've never heard a ton of benefit from better rear speakers in any of my multi-channel systems over the years. Just MHO.
I used the A'diva as rear speakers a while back. It was a large room and SPLs got big on occasion. They never complained or sounded overworked. Personally, I'd tend to disagree on spending more for rear speakers, unless you really do need more max output capability (or prefer the aesthetics). I've never heard a ton of benefit from better rear speakers in any of my multi-channel systems over the years. Just MHO.