Those Bluetooth adapters are gangsta. I paired them with some 2 pin adapters to my KZ IEMs. Nice open clear sound.
Without being hyperbolic, I can safely say the CF01 have been my absolute favorite wireless purchase this past year and I'm very fortunate that I was able to buy it through Bloom. Between my wife and children, we have about 15 different sets of TWS to rotate through ranging in price to bargain bin budget up to multi-hundred "sheesh that's a lot of money for a battery that makes noise" flagship territory. None of them give me the same level of satisfaction as the CF01 does. Sure, it doesn't have ANC, HearThrough, or most of the features that flagship TWS have. What they give you instead is a small powerhouse for your IEMs to shine on the go at a significantly lower cost of entry than a DAP. I don't know what magic pixie dust iBasso put inside the CF01, but I have run just about every IEM I own through the set and only a couple seem to stain under the pressure. Each set carries about 80% of what I get from a wired connection and that's great praise. I have to plug guys like the Tin P1 and Dunu DK-3001 Pro into desktop rigs to get better sound quality, so please don't take the 9mW rated power at face value; current delivery more than makes up for it. Combine that with a case that comfortably fits my IEMs with room to spare and plenty of cushioning (that also charges wirelessly) and this option starts to become a no-brainer. The buds connect to my phone the first time every time I pull them from the case, too, which should not be understated. Seriously...I've tried some of the best TWS and they do a pretty good job, but I'd handily trade them in for the day-to-day convenience I get with the CF01. If the only thing you're caring about is sound quality and you already have MMCX IEMs, the CF-01 should be on your short list. Improve the compatibility with a set of OE MMCX/2pin adapters and you may just find yourself rediscovering your IEM collection. Two thumbs up as high as they'll go for these guys (and Bloom). They're fantastic!