Pros: Well built, designed, and presented
Best mic/call quality I've seen
Even keeled sound profile
Battery Life, Wireless Charging
Good USA support
Wearing detection and volume control
Cons: It could be a little more articulate, especially on the sub 75hz region.
Touch control can be a little finicky, but they have smartly disabled single touch to prevent mis-touches
Well designed, built and presented TWS at a reasonable price point ($55), the Air has excellent microphones, a decent interface including wearing sensors, a good battery life with both quick and wireless charging, and IPX7 waterproofing backing its all-rounding sound signature. They would make good gifts.
Unlike most budget TWS, Earfun puts out products that are well presented and intuitive with well written instruction manuals in multiple languages. They also have (at least from my contact with them) good customer service in the US.
Starting from the outside, the case is light and slim with a nice design distinguished by a subtle dip of the top surface extending down the sides in a subtle curve. There is a single diffused dot of light that comes on when you remove/replace the buds that let you know of the battery life via changes in color.
The stemmed earbuds rest stem down, held by strong magnets that make it slightly difficult to pull them out at times, the round heads lacking an easy grip area. Opening the lid brings on the sync indicating micro leds on the outer surface of the buds that blink until connected. The connection is pretty immediate on all my devices, the buds chiming "Connected" before I get them to my ears. They remember the last device they were connected to, and can remember handshakes with up to eight devices, allowing to use them by turning off bluetooth on the last remembered device / connecting to the available device at hand if the last remembered device is not around.
They use shallow fit silicone tips with a flange and could probably accomodate the misodiko/ikko foams amongst others. The provided silicones are very thin, yet I was able to get a good seal -a task I often have difficulty with- that had them secure enough in my head to stay seated through some headbanging roleplay. Given the shallow fit, they are not the most passively isolating earbuds and I would recommend foams mentioned above if that is a concern.
The interface is touch controlled, allowing a variety of gestures including volume up/down, next song, pause/play, voice assistance. With my hands, the multi-tap gestures work best if I'm deliberate about putting as much of my fingertip as possible. Light taps of small contact surface often go unnoticed. They also have capacitive sensors that know when you take them off -most of the time- and pause/resume playback when you remove/replace one.
The microphone quality is the best I've seen yet. They have two mics in each bud, one at the outer end of the stem and one near the top of the body. I was able to stick my head in the window AC and still make a clear recording.
The sound will please a majority of general users. I would prefer a little more precision, but then, I'm an Etymotics sort of person and my other iems are all detail oriented with faster, more resolving drivers. A sweep finds 10hz deliver an audible rumble with a slightly resonant boom between 50-90hz. The drivers were well matched and I couldn't find any other issues such as driver flex / housing creak. I'm really happy getting this sort of consistency in design from earbuds at this price range. Perhaps they can tweak the onboard DSP a bit given that there wasn't that much absolute roll-off.
The buds are quiet as a mouse while on standby / in quiet sections of music, probably the quietest among the handfull of bluetooth earbuds I have at hand. They don't have noticeable delay with either device (20ms-ish on youtube), and support AAC/SBC codecs.
Having noted the lack of extreme precision, I still enjoyed listening to most genres, and benchmarking against others using my test playlist, found that simply dialing the 60hz down one db and 230hz 1.5db brought back a lot of control and dialed down the minor bass boom present in some songs (using the Android system EQ only allows 5 bands) though they still lacked some sub 50hz slam. Given all the other features, I would be happy with them for general listening.
The connection was solid on my phone and ipad both, easily allowing me to work in the kitchen two rooms down in a cincerblock apartment building. The buds are built around the Airoha AB1536 chipset. Potentially, this chipset supports over-the-air firmware updates and DSP presets but there isn't an app for them at the moment, I don't know if there is one in the works. If there was an app to control DSP / Touch sensitivity, these would be even better.
*disclaimer, while I bought them myself from Amazon to make sure that I wasn't getting a hand-picked sample, earfun refunded the cost of the purchase before I shared my review so as to not affect the content.