I just got my fenestrated "sheepskin" and elite "sheepskin" pads and i peeled the originals slowly so i can preserve them for reference... good thing i did! Fenestrated "sheepskin" sounds NOTHING like the original pads, i got no measurement rig, but i can honestly say that they make my Aeon2 closed sound like trash tier cans. They get SUPER tinny and screechy and unbearable after just a few minutes.
I slowly peeled them off the headphone and just plopped them in their box and i can say for certain they are never coming into contact with my face ever again.
HOWEVER, the elite "sheepskin" actually does work - i put them on, and ho and behold - i got an ever so slightly warmer than the original sound blasting my ears. I can live with this no problem :)
Soundstage wise i do not hear a difference.
I've been using "sheepskin" because ... they don't really feel like sheepskin. They also smell slightly chemically... not quite sure what the material is, If it actually is sheepskin they might have treated it with something for that smell to stick to them... It's nothing obnoxious mind you ... just thought i'd point it out.
I think they get a bit sweatier than the original too, it's not hot right now where i am, but i can certainly feel it's a bit more stuffy inside when i wear them.
I don't think anyone should get the fenestrated ones or the hybrid... they make the headphone worse.
And for the price ... well i honestly do not know... i think you are better off getting original pads instead.
nidus123great review Nidus, I think you got it right putting the regular sheepskin pads after reading everyone else's experiences with the other variants. My AFC's will be arriving shortly, can't wait!