I know these IEM's have been compared a lot already, but I cant really find which are best for electronic music.
I love bass, but dont want it to recess mids and highs.
I listen and produce mainly electronic music myself but I'm not familiar with SM3 and FX700, and don't have the ie8, but the 80 (slightly different signature, but close in character).
I would personally chose without the slightest hesitation the EX1000. They are in another league compared to gr07 or ie80, though, if you want a good value iem and like a more linear frequency response, gr07 is a very good value. If you are familiar with equalization, you can make it sound excellent.
I think the W3 best fits your descriptions. It has the bass, soundstage, and sparkle that you're looking for in electronic music. The SM3 has slightly recessed highs and the soundstage sounds a bit unrealistic. I have not heard the others but I would assume from reviews that the EX1000 is the most balanced, and the GR07 is pretty neutral as well.
I think all your contenders would be excellent. I listen to a lot of electronic (mostly Drum and Bass though), and had the chance to try the GR07 and SM3 V2 yesterday, and I'd place my IE80 in between them as follows; SM3 > IE80 > GR07. This is based only on quick first impressions though, take it with a grain of salt.
I was very impressed with the GR07, which sounded very clean and well-balanced with my DnB. The SM3s are amazingly good, although I'd need a longer audition to really decide what it is that makes them so much better than my much-loved IE80s.
if you like bass, the IE80s would do nicely (though I haven't heard the EX1000, FX700 or W3). Some say it's bloated, others not. I don't think it's bloated, but it's definitely got enough punch for satisfying EDM listening. Although I find generally that with electronic, soundstage matters less, the IE80s have a great soundstage too. I'd recommend them. Good luck!
I have to say the SM3 is amazing with electronic music. I personally think IEM's with good mids are the best for EDM because that's where most of the music is especially for melodic stuff like progressive and trance but they still sound awesome with techno and dub. I've tried all kinds of IEM with many different sound signatures and the SM3 is the best I've heard for electronic music, worth every penny.
I've had all except the IE8. The EX1000 is my favorite sound but the fit was so ridiculous I had to sell the thing. If I could find something that sounded like the sony and fit like a westone I'd be done.
All of the headphones mentioned are awesome. My 2nd favorite after the Sony is the SM3.
I'm almost on same boat, I'm considering um3x as well. Since I don't think I'll notice very much difference among these iems and regret my purchase. My biggest concern is the fit. I have a pair of gr07, I've tried all the tips along with the mee tips still getting uncomfy after an hour or so.
Are sm3 v2s are more comfortable than westones which I understand one of the most comfortable iems