OK, I have been listening to these for a while now and I think I have formed an opinion.
Before we have a firework display I must stress that these are MY veiws and I may well be wrong but they are true for me.
I am 53, so ears prolly are not that great.
These are my first higher end IEM's and I have not heard any others to compare.
I have though been pursuing SQ for many years.
Firstly with a home stereo. Gave up.The sound I want would cost around 10k.
Then ICE. I finally have a superb sound in my van. After years of experimentation, quite a lot of money and a very knowledgeable friend.
The music I listen to is mainly Rock. Ranging from Tom Petty Radiohead through ZZ Top, Pink Floyd, Yello. Various electronic stuff, some Blues, SRV... And of course the man in my avatar, although I could listen to him on a transistor radio in a dustbin and still enjoy.
So anyway. The IE8's have had 100hrs+ burn in. They are now markedly different to the way they sounded straight out of the box.
IMHO, Burn in was most marked after 10hrs and again after 30. Beyond that, I could not honestly say wether it is just me getting used to them. They do sound pretty damn nice now.
However. I still say that they are a dissapointment after reading such effusive reviews of them, both on here and elswhere.
Firstly, some things that I have learned about HiFi.
1) Everybody must hear things differently. I have heard really hi end rigs that I could not bear to listen to. Linn for instance. Yet other people love the sound.
2) I do not believe that you have to "get used to a sound signature". If I like something, it puts a grin on my face straight away.
Back to the IE8's. Am I keeping them? Yes. Would I recommend them? Not necessarily.
They do sound very good if you are careful with depth of insertion. The soundstage is not "immense" IMHO.
Bass is not bad but they do not reproduce much sub bass.
The bass tuning screw gives me the option of muddy or muddier.
Left at minimum things are OK. Not incredible.
Basically these have not blown me away.
I do not believe that the designers at Sennheiser intended this product to be listened to with a less than complete seal.
I do not know what they think that they have achieved with that bass tuning screw.
I would prefer a simple blister pack and a price reduction rather than the overblown presentation case that they come in, which will reside in my loft.
So why am I keeping them?
Because I think that a lot of my problem is far too high expectation.
Thinking that £200 is an awful lot of money to pay for an IEM.
In reality, I suspect that any IEM at this price point is going to be a compromise. Hopefully doing some things very well.
The 'phones suit my ears very well. Got a nice snug fit easily with the standard silicone tips.
The IE8's are really well built.
They sound way better than my CX300's!
So to sum up. Ignore the hyperbole and you may be quite pleased. That is all.