Nice sensitivity! However IMO while not a true midrange in the traditional sense, it looks like the breakup is starting after 3khz and I wouldn't cross it any higher than 2-2.5khz, where you'd still need a waveguide of some sort if directivity matching with your HF driver was your goal. Distortion specs look extraordinary between 100hz and 2khz. ATC mid dome levels. Couple 8" (sub)woofers crossed 100-150hz to this driver with a waveguided tweeter could make on hell of a floorstander.
If they bring out a midrange 4" with similar performance, we could be looking at the new possible leader in the traditional "midrange" band (300hz to 3-4khz)