Hi all, first post here,
 
I was pointed to this site by a colleague and I've found it very informative so far; only trouble is, I now have too much information and wondered if you could help me narrow my selection down further; first a little on my most recent sets:

Creative EP630 -> Creative EP830 -> BOSE In-ear headphones
 
The first two were bought on the basis of price (though the 830 I did buy as an upgrade).  Prior to these I'd been using bundled headphones which never really impressed me (always preferred to listen using proper speakers where possible).
 
I was quite happy with the EP630s, they provided more depth than previous headphones, though they did seem to give too much bass (or rather I liked the bass but it overwhelmed the rest of the music - Ideally I wanted more balance).  EP830s seemed to add a little more clarity/balance.  Neither set lasted very long though, they were rather tatty within 6 months or so (though still working).
 
The BOSE headphones seemed to provide a lot better balance, good bass and clarity, but they're not 'proper' in-ear and so provided no isolation, and they didn't fare too well on the train/tube journeys (I heard too much of what was going on around me and I was giving out too much 'noise pollution'!).  They were also horribly uncomfortable.  Anyhow I managed to kill these by wandering past one of my kitchen units and pulling the jack plug off entirely
 
So now my only working pair are the EP630s (they look in worse shape than the EP830s but the left hand phone, while working, has gone quite quiet).
 
Having gone through this thread:

http://www.head-fi.org/forum/thread/478568/multi-iem-review-100-iems-compared-westone-um3x-turbine-pro-copper-added-08-18
 
I think I've narrowed my choices down to three:

Brainwavz M2
Fischer Eterna
HeadDirect RE0
 
I'm more than happy to consider others also but those three stood out.  Now I suppose I should go over my usage; they will mainly be used with an iPod Touch (3rd Gen if that makes a difference), and occasionally with a PC/Laptop (gaming/internet radio).  I listen to a reasonable range of music: Classical (Baroque, Opera are my favourites, but I'll listen to pretty much anything), Rock, Indie.
 
I do like bass, but I also like balance and clarity  The RE0's stood out in the review most to me, but I have concerns about them because I keep reading that they need an amp to drive them (my budget at the moment wouldn't stretch to a headphone amp - I've never used one, but the thought doesn't appeal anyhow as it adds to the bulk that I need to carry around).  So that leaves the M2s and Eternas... I suspect that all three are better than what I've used up to now, but I don't have any way to compare them to what I've used in the past so not really sure what to go for... as I said I do like bass, but I don't want it to drown everything else out.
 
[edit] My budget is around £50, so I don't want to stray far north of that [/edit]
 
Any advise appreciated!

Thanks

Instead of the RE0, look at the RE-ZERO. Both are made by Head-Direct. The RE-ZERO is alot easier to drive and you don't need an amp.

Consider  Hippo VB. This are in your price range and are quite unique: you can adjust the amount of base by adjusting the sound plates.
Also hoe about Radius DDM (HP-TWF11R) .
DDMs are often compared to top tiers such as e-Q7, SM3, IE8, FX700, CK10 among few.  here; I personally listen to lots of classical/vocal music and DDM are my favorite phones due the amazing reproduction of stringed instruments.
 
There is a great review written by an English man
 
http://www.head-fi.org/forum/thread/497803/review-radius-ddm-hp-twf11-retro-on-the-go-go-go
You can get this in OEM version from Japanese dealer for around $100US or so. (musicaacoustics.com)
You can get them in UK as well but they cost double the price you are willing to spend at iheadphones.co.uk
good luck in your search.

Thanks for those RE-Zero are one to consider and the DDMs sound very nice too - particularly for the stringed instruments; I expect Boccherini and Bach recordings would benefit from these
 
I've sent an e-mail to musicaacoustics.com to request a price, and will consider both; they're a bit above my desired price range, but sounds like they're probably worth it.  Will take a look at the hippos too - never thought I'd stick a hippo in my ear though (I know that was incredibly lame, but couldn't resist)

The OEM is $109 however you do  need to buy a set of tips. Also their isolation is horrible and microphonics is not that great either although you won't be able to hear most of it when music is on.

M2, you wont like the RE-0

Here's another person's perspective:
 
http://www.head-fi.org/forum/thread/450407/multiple-iem-shootout-v-3

Thanks, what's wrong with the RE-0 for my use-case?  I see you have quite a haul of IEMs that you can compare with

I've now taken a look at this thread though:
 
http://www.head-fi.org/forum/thread/450407/multiple-iem-shootout-v-3
 
...and I am leaning more towards the Eterna's if I can get hold of Rev 1, M2's are still in the frame otherwise (and RE-0; maybe I could deal with an amp or the ZERO... I do like the look of them on paper still, but Mark's comments may push me away from them).

OK, I went in a different direction entirely, and a bit over-budget.  In the end I went for:

Ultimate Ears SuperFi 5vi
Etymotic MC5
Fiio E5 amp - quite good, but can't charge and amplify at the same time without a lot of noise/interference from the USB connection.
 
So far I really like the sound quality on both - I prefer the MC5 (but I've only really used each for 4-5 hours so far, so they're not burned in).  I like the MC5 most so far - it seems to have the most balanced sound at this stage.
 
I found getting a seal on the MC5's quite a challenge initially - took a lot of fiddling with the different tips, but in the end got a good seal with the larger tri-flange tips included with the units - I then got completely lost in the music
 
I've found it really difficult to get a good seal/isolation with the SF5's so far and I don't think I'm getting the most out of them even though I do like what I've heard so far - I'm currently using the comply tips that came with the SF5, but given that the tri-flanges seem best on the MC5, I'm figuring that I'll try to find some tri-flange tips that fit the SF5 (any recommendations here?).
 
This thread pointed at some potential ones:

http://www.head-fi.org/forum/thread/479087/found-triple-flange-eartips-for-ultimate-ears
 
Also can anyone recommend somewhere to get replacement tips for the MC5's?  Looking at the Etymotic site, it seems that the tips for these are unique to the MC5/MC3 (different part numbers at least to the other Etymotic sets) - Can I get replacements anywhere other than Etymotic direct?  I've googled, but couldn't find anything so far - ideally I'd like to get 2-3 spare pairs of tips, but at the prices Etymotic themselves charge, I'd end up spending nearly as much as I did on the phones in the first place; I'd be happy to do that for a custom fit , but I assume there are good 3rd party (or cheaper ways to get the original) etymotic tri-flange tips similar to or the same as the ones that came with the MC5s. I don't need anything yet, but would like to have spares just-in-case.