Hi All,
This is to offer a bit of a warning about who or where you get your Sony EX90s from. Recently (a week or so ago) I ordered some EX90s off Amazon marketplace. They were ~£30, so a bargain compared to Amazon proper's price of ~£50. Now I previously owned EX71s and I liked them alot. Initially they took some getting used to because I thought them too bright compared to my previous in-ear phones (but not ear-canal phones if you know what I mean). Their clarity was amazing to my ears and I had no problem with bass that some people report. When I got my new EX90s they were, for want of a better word, muddy. The mids were so fat and clouded that I was really dissapointed. However, I gave them time and thought that it might just be down to the difference between the brightness of the EX71s and the EX90s. After a few days though I just could not reconcile the fact that they just sounded poor. They also did not compare to what I had read on the internet about how good they were meant to be.
So, I ordered some more EX90s - this time from Amazon proper. It was a risk becuase it could just have been down to my personal sound preferences and I would have ended up with two pairs of headphones i didn't like.
Now the new EX90s turned up today and I am so glad I took the risk. They are great. They remind me of the 71s but just better. The overall levels are much better balanced but they retain the clarity I liked. This is what I expected when I first ordered them, not what I received first time around. So the bottom line is that some people are selling fakes. It is difficult to know who and at what price point to become suspicious. All I can say is be careful. Please don't be put off as they are great phones, truly, just be prepared to complain if they are not what you expected.
Here are some pics to help you see the differences (even if you cannot hear them). It may also help you to decide if you have been sold some dodgy EX90s.

This is an image of the documentation you get with the originals - if you have different from this, or less than this, - be concerned.

This is a shot of the case, original on the right, fake on the left. Notice the proper leather (more rigid) case.

A second shot of the cases.

This is a shot of the actual headphones. Originals on the left this time (sorry for the inconsistency). Very similar but there are visual differences.

This is a closer shot of the originals. Notice the length of the 'neck' between the headphone barrel and the tapered silver bit where the lead protrudes. Also note how smooth the turning of the barrels is.

This is a closer view of the fakes. Shorter 'neck' and rougher finish of the turned barrels.

This is a close up of the left headphone, original on the left. Note the larger bevel on the end of the barrel and the smaller black gap between the barrel and the large disk area that holds the cone (god knows what it is called).

Another pic of the fake to show the differences pointed out above and also some roughtness around the edge of the larger diameter circular bit and the black rubber cover around its edge.

A final shot of the genuine.
I hope that is all of use to someone.