I have the HD1 and previously owned the PXC 550. I'll say this, the HD1 has better sound quality than the PXC, and they both are built extremely well. I still prefer the wired HD1 because it's slightly V shaped in terms of frequency but it's very balanced. The bass is nice and it doesn't overpower the music. The PXC has better features but less detail in the sound.
I've tried the MDR 1ABT and I'll say that headphone has way too much bass and it's a bit sloppy in terms of sound quality. It also feels a bit cheap and loose. HD1 beats it in every category.
If possible, consider making yourself a lossless library. Streaming music isn't terrible, but if you compare a flac file to any streaming service, you'll hear the difference easily. Lossless has better dynamics and will sound more balanced.
As far as the options you've chosen, I'd vote for the HD1 by far. You can probably even do the wireless and just use the wire unless you absolutely need Bluetooth. No reason not to have both options. HD1 definitely opens up with a mobile amp. I use the FiiO X3 player and A5 amp and it helps smooth the bass and tighten it, making it punchier and more balanced. It also helps the dynamics. Good luck choosing!
