So, two things, I received one of my orders from Gearbest for three earphones, two of which were KZ ones, the KZ ATR and the KZ ZS1.
First things first, they both are good sounding earphones that rival the ZS3. The ZS1 feels like you are wrapped in a blanked of warm bass but it doesn't muddy up details, it just makes everything sound fuller whereas the ATR provides a more intimate but still warm-sounding listening experience.
Having listened to the KZ ATE and the ATR for a few hours, and recalling the comments some people made here about the ATR being a natural upgrade over the ATE I'd like to say I respectfully disagree. I think the ATE's sound signature is significantly different from the ATR's and they provide some sound features that are better than the ATR's, specifically their soundstage and imaging. Also because the sub bass is not as pronounced as on the ATR, it's easier to discern smaller details on songs, particularly noticeable on live recordings.
I think that for the money the ATR is a better purchase than the ATE in terms of value, but I don't think they are a superior earphone to the KZ ATE, they offer a different type of sound but I can understand why a lot of people would prefer them over the ATE as they have a warmer signature.