My KZ-ZS3 has arrived. First thing that immediately occurred to me is when connecting the cable, give it a solid push. I mean, really get in there. Initially I pushed it to where it felt secure, the amount of pressure I'd use attaching my 2 pin cable to my Mojito, but audio kept cutting out any time the 3.5mm jack rotated due to movement. Also, it's a fairly microphonic cable, even considering the over-ear configuration. Comfort-wise, I always hope an IEM will disappear so I don't even feel like I"m wearing something, and with the shell of the IEM that's true, but the nozzle & tips retain a feeling of pressure on the canals, and I'm using the smallest included tip. Most of my tips that I'd normally try out are either too big or too little, so I'm just going to keep stock tips on for now. I do not see these being comfortable enough for me for a several hour listening session.
Keep in mind all that's to come is with zero burn in as I just got these in the mail before I headed off to work for the night, so this is that fresh out of the box sound. Sound-wise, there are here for bass. I remember for awhile, JVC was the route to go for a $20 bassy IEM, but I think I like this sound more... although my JVC has been in a box for awhile and we all know how good memory holds up for sound. It reminds me of the Sony XB500, but with better mids. As far as those mids are concerned, the vocals aren't bad, but they can and will be overshadowed by bass if it's present. Detail-wise, I'm not impressed... it might be roughly middle of the road, but I"m unsure. It's a fun IEM, but it's by no means analytical. For orchestrated music some instruments seem to get lost in the background. The treble sounds fine so far, and I haven't heard anything piercing so far. I'm by no means treble sensitive, so gear that some have gotten rid of due to high treble I haven't been bothered by. All in all, so far I'm liking them more than the KZ-ATE and ER2, and I never gave my ED9 a listen as I bought it purely to steal filters for the earphone that can share them. I should remedy that soon.
As far as the recall goes, I'm not noticing anything wrong with it so far, but again these are fresh out of the box so who's to say what will go wrong in the next week, month or not at all.