Unfortunately I have not auditioned the Soundmagic E10. But, I should be able to answer your questions from a general perspective.
1.
Microphonics: The O16 features a tightly twisted cable sheathed in plastic which retains shape memory to an alarming extent. But microphonics are surprisingly low even worn cable down. Lowest I've experienced in an IEM. Also, non-existent when worn cable up.
2.
Open back design: Yes, being open back, the isolation does suffer. Okay, that is an understatement. Isolation is very very low but this is inevitable and it does pay off in the soundstage department. This IEM is not meant to be used outdoors or even in a mildly noisy enviroment, so poor isolation is not a negative trait.
3.
Sound signature:
This is still early into my review process therefore it could be subject to (slight) change.
In general, it exhibits a balanced/fairly neutral sound signature with a slight mid forwardness. End to end extension is good with very mild roll-off on both ends. The treble is laid back and non-sibilant but conveys sufficient treble energy through some well controlled peaks.(People who like prominent treble will be disappointed). Bass extension is good and rises gradually into a midbass hump which keeps the signature natural and warm. It does lack slightly in Impact and punch(and loses some detail), which I think is a result of the venting design. The mids are fairly accurate and is linear across the range. The only drawback is that it occasionally suffers from slight unnaturalness (vocals seem stretched). This is due to the boosted soundstage.
The sound stage is it's main strength and works very well with live recordings(which is what it is meant to do). However poorly recorded tracks will suffer a bit.
Overall, I think it is a very good and enjoyable IEM that doesn't particularly emphasize any region of the spectrum and provides the widest soundstage I have heard in an IEM (more than my Brainwavz R1). It does have a few quirks but it does not manifest on every track. At the early bird price, I think it is a very very good deal and not to be missed if you are on the lookout for an IEM that does what the O16 advertises.
@RD274 : Sorry, I haven't heard the Brainwavz M4.
Since I have not heard the Soundmagic E10 or the Brainwavz M4 I cannot say for sure if you will like the O16.
It is far from the conventional U/V shaped signature and is not to be considered as a fun IEM(which requires colouration). The O16 delivers on what it advertises.
Let me know if you have any more questions.
Listening info:
Reference IEM: HiFiMAN RE400
Files : Above 320kbps, mix of all genres. Also, many live recordings were tested
Listening volume: -25db on sansa clip
Tips: Hifiman bar tips
Source/player: Sansa clip, LG G2, Asus ultrabook.
