I just came across something even the basic and cheapest drum computers handle correctly: when playing an open HH, changing to a closed or half closed HH should mute the open sample. Drums sound rediculous without this.
Also, the “Who Groovekit” loops actually do not loop cleanly rendering the entire sample set useless. 
I have seen the hihat muting issue raised before so i am sure they are aware of it.
I just tried the Who Groove loops and they sounded fine - you are setting the tempo to 130 aren’t you, as the audio loops need to be played at the tempo indicated, there is no time stretch (yet?) to make them fit any other tempo.
In that case I can just delete the entire audio loops, this is rediculous for an app that claims the professional level. With more and more glitches starting to pop up I really start to wonder if Steinberg are aware that even though this is “just” an App people would consider using it aside the Sunday-afternoon-goofing-around level. I would pay 200$ for a mobile AW that integrates seamlessly into my studio without such facepalm cutbacks. This is not a toy…
Thanks Phil for delivering the bad news…I now have to feed you to the lions 
Well at least i got to use Audiobus before being eaten!