It feels really good to hear that the expensive models have mostly the same flaws as the cheap ones. So the people who tell me it must be my 40€ anker models, because theirs always work fine probably just don't use them as much, but at the same time, spending more money would not have given me better functionality (except noise canceling).
I guess the real thing to take away is, that cable is still the most reliable option (and also saves a lot on battery!)
Edit: I have a pair of JBL LIVE300TWS. They're good!