Right now they sound so great, I don't even want to mess with it.
They come shipped with 100% fill level. I believe the only thing removing the fill will do is maybe expand the soundstage and image a little, which is not a big deal for me.
Last night I was listening to demo track#1 (comes with your Philharmonic speakers) on my Phil3. I thought my KEF 201/2 surround speakers were on! Creepy.