Different kinds of product: one is active with its amplifier built in, the other passive and needs one. Judge them on how you want to own the system, not just the specs.
| Area | Better | Why |
|---|
| What you buy | depends | Sonos Era 300 2 pack is a complete system - just add a source. Klipsch RP-600M also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | With Klipsch RP-600M that all comes from the amplifier you pair it with. |
| Upgrade path | depends | Klipsch RP-600M can be re-amped later and outlive several amplifiers; Sonos Era 300 2 pack ages as one unit. |
| Size | depends | Sonos Era 300 2 pack is easier to place; Klipsch RP-600M is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | B | Klipsch RP-600M: bi-amping. Klipsch RP-600M sits in a wider range (17 models), so a matched surround system is easier later. |
| Price | B | Klipsch RP-600M is cheaper - $459 against $758, about 39% less; arguably a different class. Speakers only - an amplifier narrows that gap. |
A Sonos Era 300 2 pack B Klipsch RP-600M
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Sonos Era 300 2 pack suits you if you want one box, ready to play, with nothing else to buy. Klipsch RP-600M suits you if you already have an amplifier, want to choose the electronics, or expect to upgrade in stages. Neither is the better speaker in the abstract. In a large or open-plan room, Klipsch RP-600M has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Sonos Era 300 2 pack is the easier speaker to get right. Think about the whole system, not just the speakers: the roughly $299 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.