I have Qobuz & Amazon Prime HD, both which play 24-bit. The sound quality on Qobuz is superior to Amazon by a modest margin IMO but it's only really discernible when listening through good hardware. However, Amazon's library is pretty hard to beat, especially for rock and electronic - after all, Qobuz started out as specializing in classical and jazz, so its library in those genres is second to none but they are improving in all other genres, and especially with newer releases).

For me, it's worth keeping both. If I have my good headphones on at home or at work, I'll always search Qobuz first, then Amazon in order to get the optimal sound quality. For on-the-go with my bluetooth headphones, Amazon is my go-to because I'll usually find what I'm looking for without having to futz around with multiple apps, and the quality is indiscernible with that setup.

FWIW, if you check around in audiophile forums, the consensus regarding sound quality seems to be Qobuz > Tidal > DEEZER > Amazon HD > Spotify, but I doubt you can go wrong with either Qobuz or Tidal.