Which robot vacuum offers better value: the Dreame D20 or the Roborock Q10V?

The Dreame D20 costs $200–$300, half the [Roborock Q](https://www.amazon.com/s?k=Roborock+Q&tag=wehavethat-20)10V's $400–$500, and cleans just as well. The Roborock brand tax is real — you’re paying for the name and ecosystem, not better performance.