Thank you all for your kind advices.
I own a 601 of which I like the open sound sig very much but the thing hisses like crazy, so a no go.
Think I remember reading somewhere this happening more often with this device.
That's why I suggested maybe Hifiman in higher end version as an alternative.
Haven't actually looked into details yet, so didn't know yet about heat, size, battery time, UI, etc.
Kind of a big price to pay for the (probable great) sound sig.
Am kind of hesitating to reveil another thing here but will do it anyway, please don't shoot me.
After amping the Tera with the Vorzüge II, I A/B-ed this combo numerously with my rockboxed Clip+ in
default sound settings and actually was hardly able to tell the difference, Tera just being a bit more spacious.
Probably my 52 years old ears are giving up on me but then again, if that's my situation....
Clip+ is even smaller, has reasonable battery life and can be EQ-ed nicely to match the GR100 perfectly.
But the Tera is still looking at me right now...
Maybe other IEM's after all