I don't use an iPhone but Gryphon for me is more about use case. It's significantly more powerful than the Walkman, so if you need to drive full-size headphones, Gryphon is a better choice. I'd have said Gryphon's Bluetooth input offers great versatility and sound quality, but since iPhone is AAC only, it's not anywhere near as good as LDAC from an Android phone. Still, if you're listening casually, it's nice not to have wire Gryphon to your phone.Thanks for this and worthwhile considering - only issue I have and which is swaying me towards the ifi is the fact that a good % of my music is live recorded so not the best sound in the first place. So my thoughts were as a best of all options the ifi maybe the better fit.
I haven't actually directly compared the SQ between Gryphon and the WM1Z, though I expect the Walkman will be superior technically and probably musically too. That said Gryphon is an outstanding sounding device, and at $600 an absolute bargain imo.