@donavabdear
You’re right, self noise cannot be completely ignored. Some even advocate high-end isolation stands like HRS or Critical Mass for headphone amps. However, in my experience while isolation has made a big difference for my turntable & speaker setup, it’s not so much for my headphone setup. I have a very high end T2 electrostatic amplifier (massive tubes & SS hybrid, quad of EL34 and quad of 6922 plus a ton of OOP high voltage silicon), and quite honestly hear no meaningful difference between it on or off a Critical Mass Black Platinum shelf.
Maybe of impact in some cases - but for most cases, the self-noise energy will be a few orders of magnitude below the energy received from some big nearby speakers. But then, who knows - maybe it’s a bigger deal than I’m giving credit to. CMS would probably say I really need their new CenterStage feet (in addition to the shelf) to help defeat self-noise. But feet that purportedly required hundreds of hours burn in (sounding BAD for a lot of the lead-up to that) are just a no-go for me.
I borrowed a Stellia and liked some aspects of its sound, but it’s a bit too bright for me with SS amps. I liked the Utopia better - that headphone also sounded quite good right out of a Naim integrated amp.