Ask HN: Which landline phone do you use?

All of our company members work remotely, so we spend a lot of time on the phone. We're always looking for the dream phone setup. We don't use Skype, because although its sound quality is fantastic, it's not reliable enough. Its poor reliability becomes more noticeable when there are many people on the call. Do you have any recommendations for great landline phones—or landline headsets?