It's tough to say which speaker system is better, Bose or Sonos. Both have their pros and cons that make them appealing to different types of people. It really comes down to what you're looking for and what your budget is.
Bose speakers are known for their superior sound quality. They use proprietary technology to create rich, detailed sound that fills any room. They're also very durable and easy to set up. However, they can be quite expensive, especially if you want a multi-room system.
Sonos speakers are less expensive than Bose and still deliver great sound quality. They're also very easy to set up and expand into a multi-room system. However, they don't have the same level of durability as Bose speakers and some people find the app interface confusing.