It is a pleasure to read you, Etydave. Your posts, despite you being an engineer at ER still manage to come across as totally honest.  I have long been a happy owner of the 4S, they have given me so much pleasure. I tried the 4P and truly disliked them. They defeated the purpose in my view...

Thanks Ozkan, I checked but the MK5 are a 1/5 of the price of the ER4. and from the same manufacturer. So unless Etymotic has gone mad, I can't see this as an upgrade to my ER4. 

Exactly! The others go with 6, 8 10 drivers... and Ety sticks to their old mono driver and yet they are still hard to beat from what I can understand.

SKOOTB, I see you're coming from an ER4 as well. How do you like your K10? Would you say it is an impressive upgrade over the ER4 and their detailed presentation? Worth the money? I am interested to hear it from people that have made the leap. thank you!

Hi, I have exactly the same issue as MrGuzmanWhite. I have had the pleasure to use the ER4 for many years, had them customised with silicone and I would love to find a CIEM that is superior, both in clarity and adding perhaps a touch of bass. I see all these fancy IEM coming in the market with...

  So in other words, you bought a pair of X2 that you find pretty dull, "middle of the road, mid-fi"  and certainly disappointing in comparison with your other high end cans... for what? just to write this review? I am getting confused, why not return a pair of new headphones that doesn't bear...

So in other words, you bought a pair of X2 that you find pretty dull and certainly disappointing in comparison with your other cans... just to write this review? I am getting confused, why not return a pair of new headphones that doesn't bear a single positive advantage over those you already...

Yes $700 in the US. And £550 in the UK. So the equivalent of $886. Such a rip of. Where is the difference going? in the importer's pocket?

I read some of these posts. Let me share my experience with the ER4s. I have them for such a long time now and they never disappoint. I have always been curious to see how the other highend in-ear fare against it but by the very nature of things, it is difficult to experience in-ear monitors...