Got my KZ ZS1 today. they remind me A LOT like the Tennmak Pros, the pros maybe being slightly leaner and the ZS1 having slightly bigger soundstage and more forward vocals.
In terms of the ZS1 vs ATE S.... ATE S wins. The ZS1 is clearly more refined, has clearer mids, much better crispier treble detail, bit bigger soundstage... BUT it doesn't have the smoothness and warmth of the ATE S. The bass on ATE S although slightly boomier and less controlled still sounds more fun and musical. it also does kickdrums like no other IEM
The ZS1 just like the Tennmak Pros may be very detailed, but they are quite clinical and too 'clean' sounding (for me)... which lots of people will prefer. the ATE S though is like the 'little engine that could' lol.
What i will say of the ZS1... vocals sound AWESOME on it, helped by being pushed forward. male and female vocals are near enough perfect to my ears.