In advance I apologize for this rant. Still I think it's impressive to type this much on an iPhone. Imho the She3570/80/90 (supposedly the same driver and design) needs some getting used to. Haven't reached 100+ hours on mine but they're detailed and crisp. To start from the bottom the bass is incredibly extended only rolling off below 30Hz and without midbass boost. Not bloated at all. Decent in speed and with just riddiculous sense of impact. They sound like a lower quality GR07 on steroids just lacking in texture and that lovely organic feel that makes drums sound... like drums. The bass is not like most bass enhanced phones because it appears to be linear rather than midbass boosted.
The midrange can feel hollow but that's also a matter of taste, the emphasis is on higher midrange rather than lower, making them sound a bit hollow and cold but still detailed and enjoyable. To my ears they carry some energy in the upper range but distorted guitars sound somewhat edgy and they lack in body compared to something like GR07. Still with good details (keep in mind they're basically worth what you munch on an evening with two movies).
What makes these phones unique imo is the extended treble. They too carry a good deal of details and have sparkle enough for most people except treble heads. There is some sibilance in the upper mid/lower treble range that's revealed by running a few frequency sweeps or listening to sibilant records, still a lot less than my Akg K271 mkII (might be resonance in my ears due to the circumaural design). That should be the cause of some details getting lost to some harshness.
Soundstage and separation are two things I'm not very good at describing but the soundstage is well on par with average iems and separation is good for budget iems.
That's me just reporting what I hear. Comparing to what I know. Comparing them to Beats by Dre Tours (bought cheap used), Heartbeats by Lady Gaga (bought on sale), Bose IE (sale), Meelec M9, Metro fi170, iBuds or other generic iems/earbuds they simply sound a lot more refined. I can appreciate a lot of different signatures so no immediate bias here. But coming from these other phones none of them offer detail threatening that of the Philips'. The bass is deep and refined at the price point and beyond. Like a miniature GR07 that tries a bit too hard. The only harshness, after some listening, is the upper mid/lower treble where some spikes are present.
The overall presentation is bright with a great bass response at the bottom. Sorry for the rant, I just like these phones. Might be of some value that I haven't heard of the others, I can only vouch for the Philips. And oh how I vouch. They're awesome after realising what they are.