I have now had the NuForce trial NE-700X for a few weeks, and have done some listening. Take this fwiw
Build:
The NE-700X has a great feel of good build quality, they feel sturdy with the metal casing, unlike my previous main earphones Shure SE-210. The soft tips are easy to replace, but there is no risk of them falling of. I usually like tri-flange and bi-flange tips, but with these NE-700X resorted to use the medium sized regular tips, even if tri-flange was supplied. The Tri-flange worked well at first, gave the best isolation and felt good, but it was hard to find a good fit that held tight when walking or working. I think its that the tri-flanges rubber is thinner than my Shures and thus will not hold as tight as good. The tri-flanges are not unusable, i just would like to find that the tight fit would hold better. With the normal medium tips i had good results, even if less bass than with the tri-flanges, it was easy to find a good fit that held even while crosscountry skiing.
Isolation:
With the triflange the isolation felt just as good as with the SE-210. With the regular tip, i found no difference to the RE-Zeros, about isolation, but not as good as with the triflange.
Sound:
As i have no extensive hifi background or equipment, i used for reference what i had. I used for sources a iPod Nano 1st gen. with RockBox and a HifiMan HM-601 both coupled with Grado HF2 and same songs. Most of my head-to-head comparing was done with this track: "Hocico - Forgotten tears". The song has a punchy bass that leaves a presence of hum and a strong bassline as well as a lot of high-hat percussion.
First without burning in, i thought the NE-700X had a bit too bright and piercing treble, but after a few days of burning the songs felt just right. The song has a punchy bass that leaves a presence of hum and a strong bassline, and the NE-700X did well.
NE-700X vs Shure SE-210: The NE-700X has more bass, more treble and feels more alive. The Shures feels quite lame in comparing.
NE-700X vs RE-Zero: The NE-700X has more bass (with any tip), and its quite controlled and good and sounded best of the three earphones with that Hocico song. The RE-Zeros had really good and controlled bass, it was just not as pronounced and felt thus a bit lacking in some songs when doing head-to-head comparing.
NE-700X vs Grado HF2: If such a comparing can be done... but i felt that of the three earphones the NE-700X had a similar feel to the sound as i got from the HF-2. The HF-2 are more precise, and in that area the RE-Zeros came closer to the HF-2 than the NE-700X.
Conclusion:
Not sure i can say if i like the NE-700X more than the RE-Zeros, they are quite different but both really great. I was first quite suspect over the NuForces but they really proved me wrong. I like them more than i had thought i would, and have to test more to re-confirm if the tri-flanges still might be for me or not.