So I've been using the CKS5TW for a few days now; time for some brief first impressions. I've added some real-life pics for your convenience.
CONNECTIVITY
BT 5.0 is actually very stable. Sometimes, when connecting to a new device, the left earbud doesn't connect. A quick drop in the case, getting them out and auto-reconnect does the trick to fix it. I've had zero drop-outs in the meantime, so I'm very happy.
MIC QUALITY
I'll be using these in the office, so will make calls with them over both skype and my mobile phone. In both cases, the people on the other side were able to hear me perfectly fine (even when using them in an office space). The call audio is routed to both earbuds, which is very nice. Also, a family member said that (using them with my iPhone) my call quality was on par or even slightly better than when calling without the use of earphones.
SOUNDQUALITY
As far as the sound quality goes, I can say that I'm quite happy with them. The sound is a bit bass-heavy, but not to the point where it messes too much with mids and highs. Soundstage is so-so, but better than expected from this type of IEM. I think the larger driver really helps here, as I do find the IEM with smaller drivers (I've owned the WF-1000XM3 and RHA TrueConnect) terribly congested in terms of sound(stage). What I can say up until now is that I've never been craving extra detail, and I'm quite enjoying the low-end 'oomph' in the high-fidelity presentation these do (if that makes sense). If anything, I'd long for a bit more airy-ness but I'll have to do more listening to get a better image of the sound quality (especially compared to other gear).
For now: very happy, and like them better than WF-1000XM3, TrueConnect and E8.