Now, my perception of how they sound (100% objective on my end):
I'm a noob when it comes to audio lingo, understanding terms and being able to properly convey what I want to describe but I will do my best.
I noticed right off the bat that my music felt suppressed, though I could not put my finger on exactly what. I shuffled through a variety of genres and eras of music and came to a consensus in it's infancy:
1) vocals and melodies sound stuffed at their apex / or volume limited - like hearing music from the room next door.
2) I hear instruments and sounds that I never heard before on any IEM/Can/Speaker (attributed by the U sound-sig perhaps? or testament to quality?).
3) Bass is cleaner and less enveloping than my EQ'd CX-55. They sound more separated opposed to being the milk in my cereal. The cereal flakes being instruments and sounds (confusing? lol).
I learned a lot in the passing day - listening and reading opinions in this thread. dbdynasty brought up driver flex, a term I've seen before but finally read up on it's meaning. I can say that I've experienced it on both sides while using the foam tips. Now for my break down of specific songs in relation to my old CX-55:
1) Come rain or come shine - Eric clapton & BB king: Main Guitar doesn't stay in the air. Each note starts clean at the guitar pick but feels stuffed at the apex. Supporting instruments are clear and sharp - many of which I didn't notice on CX-55. King's vocals on this track are not as broadcasting as Clapton's, in my mind he was sitting at stage right-front but behind a barrier that makes him sound stuffy. Clapton's vocals are prominently on the left side, but once again, I'm sitting front row and hes a few feet away from me, but he battles with an obstruction ("I'm with you always" comes out as "I'm with you alway")
2) In too deep - Kool G Rap: Main melody requires some selective hearing. Vocals sound magnified (almost distorted) at inception but are stuffy at apex. Words and syllables similar to the 'S' sound in "Snake" are very hissy.
3) Killin It - Krewella: For the most part this dubstep piece is satisfactory, but the vocals - although less stuffy than the preceding examples - feels like a step too far from the mic.
4) Thriller - Michael Jackson: The creaking door sequence was pleasantly rich and 3D like ( I assume it benefits from the U/V sound-sig). Michaels' vocals are naturally soft on this track to begin with, and even more so with the R1. Continuing with the trend, supporting instruments are much more apparent and clear.
What I can say so far is that the R1 has a separated bass that compromises mid-melodies and vocals for many tracks. It's not necessarily a bad thing, melodies and vocals EXIST, the design simply gives more room for a cleaner sounding bass and the apex of melodies/vocals don't hang in the air as obvious as other IEM/CAN/Speakers. Not all songs are affected though, specifically instrumental/bass aggressive tracks where nuances do not contribute to the heart of the track. Though I'm pleasantly surprised to hear supporting instruments/sounds in many of my songs that are totally new to me. Please feel free to contradict my statements or add to them. I stand only behind myself and speak as objectively as possible. Sorry if I'm not thorough or not easy to undestand.