https://www.stereophile.com/content/mayfly-mf-201-loudspeaker

The 201s’ internal skyline diffuser succeeds not just as an intriguing novelty but as a factor in the excellent sonics these speakers produce. How big that factor is, only Trevor May knows. It would be impossible for the rest of us to say until we listen to the standard MayFlys as well as to a neutered version, with that complex wave trap cut out and replaced by, say, fiberglass or acoustic foam.

Not that it matters. For all anyone cares, the enclosures can be filled with tea leaves and old sneakers, as long as it sounds good.

Happily, the sound of the 201s—diffuser and all—varies from very good to stellar. Though slow to quicken the pulse, these speakers are not shy or retiring, but you may have to take the time to find the right placement. Yes, sometimes I found myself wanting a little more bite from the MayFlys, to really convey the brainstem-shaking power of Led Zeppelin’s “The Lemon Song” or Rage Against the Machine’s “Bombtrack.” Then again, with 95% of the recordings I played, muscular rock included, the MayFlys were satisfying and often beguiling. I won’t compose an Iliad to sing their praises, but they garner an easy recommendation.

https://www.stereonet.com/au/reviews/devialet-phantom-ii-98db-stereo-wireless-speaker-review

In the Phantom II 98dB, Devialet has succeeded in taking all the quality and character that made the original Phantom speaker so good, and managed to significantly shrink it while still retaining its very high performance. The Phantom II has been elevated to true wireless hi-fi status by introducing the ability to stereo-pair these units. Incredibly, despite the ear-pleasing performance, it’s still the striking aesthetic and unconventional bass driver design that makes it a talking point in any room – and thanks to its wireless integration, every room.