I own Q100 , Sierra2 and Sierra Towers w/ RAAL. I like my Q100 but they're still not as clear sounding and also struggle if you try and play them loud in a medium-small sized space compared to the Sierra2.
I definitely agree the terrible falls off very significantly if you stand up vs on...
Just picked up a HP-1 from a seller on Reddit. Supposedly it’s the same unit Amirm measured.
So far it sounds great! I’m going to drag it to work and compare with the 789. Not really a productive reply but I’m excited.