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 |
|---|
| Bass | A | Edifier MR5 digs deeper - 46Hz against 58Hz. |
| What you buy | depends | Edifier MR5 is a complete system - just add a source. Polk R100 also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | Edifier MR5 has Bluetooth built in. With Polk R100 that all comes from the amplifier you pair it with. |
| Upgrade path | depends | Polk R100 can be re-amped later and outlive several amplifiers; Edifier MR5 ages as one unit. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Polk R100 sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | A | Edifier MR5 is cheaper - $350 against $649, about 46% less; arguably a different class. And that is the whole system. |
A Edifier MR5 B Polk R100
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?
Edifier MR5 suits you if you want one box, ready to play, with nothing else to buy. Polk R100 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. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 58Hz anyway, so judge these on the other rows instead. 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.