Need a fast reply: £50 to spend in Sony Online store, EX700's, ZX500's, V500DJ's or NC7's?

Hello there guys!

I have an urgent question. I'm quite an audio lover, and always had Sony stuff (because it's quite easy to find in Belgium, unlike most other brands). My VAIO took ages to repair, and as a compensation from Sony I can spend £50 on their site (sony.co.uk). Even if items aren't in supply I can still get them, they use a different supply set.

What I like in earphones: an open sound. When listening to orchestrated music I like it to feel like I'm standing in a huge concert hall with excellent acoustics, good to make out every sound. I also quite like dynamic range. And a balanced sound, no Beats for me.

I have had:

Sony Walkman A815 - loved this in sound quality, usually bumped up Clear Bass on +1, and left everything else default.

Used with: MDR-EX082 - the start of my love for in-ears, really liked these.

After both my walkman and those earbuds broke in sort of the same week I bought:

MDR-EX300LP's - quite nice, but I feel like they're not as clear as the EX082's in a way, and don't really like the highs.

NWZ-X1000 - quite happy with this too, but again has a little less clarity than I'd like, but this might be due to the EX300LP's. I strongly prefer the sound from my laptop, it just sounds more clean. On this walkman I usually bump the Clear Bass by 1 too, and one of the last EQ sliders too. 

EX300's are starting to fall apart (literally) now too, after 1.5 year of heavy use.

Always used Clear Audio on both walkmans, always disabled dynamic normalization. Always used Clear Stereo too, even though that might be mostly a placebo thing.

So, now I have the choice between the following. Listed in the order of my preferrence:

http://www.sony.co.uk/product/hpi-ex-series/mdr-ex700

http://www.sony.co.uk/product/hpo-classic/mdr-zx500

http://www.sony.co.uk/product/hps-extra-bass-and-dj/mdr-v500dj (though not if they are too V-shaped, which I don't know)

http://www.sony.co.uk/product/hps-travel/mdr-nc7

I first had a look at the EX310's, but they're out of stock. Didn't notice the EX700's though. The fact that I can get them even though they're really worth much more than £50 is quite tempting. I also come from in-ears and quite like them, I always feel like they give a more balanced and clear sound than regular cans - even though I don't have any experience with any proper headphones.

Any ideas? Other sub-£50 suggestions from sony.co.uk are also welcome ^^

Thanks

- Ambroos

Just to note, I strongly prefer the EX700 over the others, but I have to make a list should the item I want not be in supply... After some thorough Googling I found out the V500DJ's suck, so those are going out.

Edit - sorry, didn't know what forum to post it in since it's not just limited to headphones but also includes in-ears, so I picked something that looked like a more general forum. To any moderator: feel free to move it!