I'd kinda like to hear Momentums that are broken in and on a rig they get along with. Shelly's pair were straight out of the box and it was hardly love at first sight with my portable. Portable stuff is still finicky. Nobody's gotten it quite right yet.
Musings aside, I think the point that portables should be heard with stuff meant to be used with portables - which the Momentums are - is really well taken.
I'm optimistic. Hi-res DAPs are selling by the boatload - by audiophile standards, anyway. CDBaby is selling FLACs. The crappy headphones I see on heads at Urban Brew are getting a little less crappy. Kids are buying records. The other day I found an intern cutting video with a pair of Shure SRH 440s on. Quality is edging toward the mainstream. The real main part of the stream will always be garbage. It's the littoral zone where there's life.
Remember the "good old days". Most people listened to scratched LPs on systems that couldn't aspire to reach absolute crap status. Or cassettes that were dubbed at ten or twenty times speed. And yet, they still manged to make enough records that sounded good enough that we could enjoy them. Win or lose, this Pono thing is bound to help.