I suggest you skip any sort of soundbar, based on what you have already state regarding your current gear, and your concern regarding both type & quality of sound produced. Nearly any standard modestly priced 5.1 system would be able to provide better sound than either the Bose or Sonos. It would help however to know what actual gear you current have (all makes/model numbers) so we can determine all possibilities that might suffice. And if your current AV receiver lacks digital inputs, upgrading that would make the most sense to be able to enjoy your current speakers, and potentially add proper surround sound at an equivalent price (or likely less) than adding either the comparably deficient Bose or Sonos.

FWIW, Sonos & Bose Cinemate are both overpriced too for the sound quality they provide. More for folks who want form over function.