Sorry to intrude, I'm a non-audiophile myself but I found this thread when I was looking for some "decent" (but cheap) headphones to use whilst commuting. It is entirely your fault that I have ordered a set of these off eBay...!
I have just exchanged a couple of emails with Paul from Radiopaq Product Support. He said (as has been mentioned in another thread) that he is unaware of any fake Radiopaq headphones being sold and sent me some pictures of the headphones and packaging.
The original packaging is the "crystal box" that urpoxi got, they moved to a more "eco-friendly" clamshell type pack in response to suggestions. The printing on the headphones has changed and the cabling on the later ones has a braided sheath. Paul told me that there were no changes to the construction of the headphones.
You can see for yourself at http://www.radiopaqproducts.com/custom_tuned.htm. (there is a zip file of high resolution images available to get a really good look)
Looking at these pictures and the ones that paul4400 took I can't see any differences at all, suggesting that his are the real thing.
Could the difference in sound be down to the mic & remote controls in the iphone version?
When my set turns up I should be able to give you a pretty informed idea of the construction, if not the audio quality.