I set the LSX IIs up on my bookshelves on a Sunday afternoon, fed them a familiar album, and sat down expecting to be mildly impressed. What I got instead was the small disorienting moment where I could close my eyes and point to where each instrument was sitting in front of me. That doesn't happen with most wireless speakers. It barely happens with a lot of passive bookshelf speakers paired with a competent amplifier. It happened immediately with these.
What KEF got right is the Uni-Q driver, which puts the tweeter at the acoustic center of the woofer so the high frequencies and the midrange come from the same physical point. The technical justification is that this creates a point source for the sound, and the audible result is that stereo imaging on these speakers is uncannily precise. A vocalist sits between the speakers rather than smeared across them. A guitar comes from a specific location in space. If you've ever sat in front of a well-set-up pair of monitors, you know the effect; if you haven't, the LSX II is the cheapest way I know to experience it.
The connectivity is the other half of the case. AirPlay 2, Chromecast, Spotify Connect, TIDAL Connect, Roon, Bluetooth, Wi-Fi — fine, expected. But the back of each speaker also has HDMI ARC, optical, USB-C, and a 3.5mm jack, which means a single pair of LSX IIs can be the speaker for a turntable, the speaker for a TV, the speaker for a laptop, and the streaming endpoint for the household, all at once. I replaced an amplifier and a soundbar with these and the room is quieter for it.
The trade-offs are real. The drivers are small, and the bass drops off in a way that matters more if you listen to electronic music than if you listen to jazz. KEF will sell you a wireless subwoofer for the gap; I haven't needed one, but I also live in an apartment where my neighbors would prefer I don't. The multi-room story is weaker than Sonos — KEF Connect works, but it does not work as smoothly across rooms as the Sonos app does. And the placement matters. These reward being put on stands at ear height, six feet apart, with some distance from the wall behind them; on a bookshelf with stuff in front of them, they sound fine but not transformative.
The last hesitation is the price. Fifteen hundred dollars for a pair is a lot for two small speakers. It is roughly what you'd spend on a competent set of passive monitors plus an integrated amp plus a DAC, which is the comparison KEF is actually picking. On that comparison the LSX II is competitive and easier to live with. On the comparison against a pair of Sonos Era 100s at $500 it is not the better value; it is the better-sounding choice, which is not the same thing.
Verdict: Buy this if you would otherwise be building a stereo system and you'd rather not have a rack. If you want streaming convenience and multi-room first, Sonos is still the easier answer.