CCS Omnibus Dark Horse edition. The best quality for the manga. Hopefully they get it again or Kodansha does a better job, because you can't get the Dark Horse version anymore.
https://mega.nz/file/1pUgwQYI#In-xA6ZRPz2kocvayCMzZ-nQC5b8zzNcFWEPYFh37Po