I just received 2 OBS Sub tanks. 1 standard 24.5mm sub tank and 1 mini 23mm sub tank. They are identical except for the larger diameter and juice capacity; 5.3ml capacity vs. 3.5ml.
Machining, fit and finish is average compared to other sub tanks I've had.
Airflow is ample and relatively quite at all settings. No detectable whistling.
Both tanks came with 2ea. 17mm .2 ohm OCC wicked SS Notch coils. Not sure of the SS wire type. Works nicely in 304SS TC mode set to 450°f.
Washed the tank parts thoroughly and flavor seems good but I'm detecting a faint machine oil taste. Hopefully that will go away after a tank or two.
Perhaps
@Roadtrip635 can chime in with his take on this new offering from OBS.
More later.
ETA/Updated: The notch coils are SS. Possibly 304ss.