I already have the 7550. In fact I will return it too.
I purchased a bunch of IEMs from Amazon to try out and keep the best.
I purchased the Westone 3, Westone 4R, VSonic GR07 Bass Edition, Sony 7550, Shure 215-K Black, VModa-M100, and Audio Technica CKS77.
Here is the rankings (Top is the best sound quality for me ears):
1. Sony 7550. Best sound I have ever heared in an IEM. The reason why I will return it is because of the cable being too long and thin.
2. Westone W4R. They sound good but the bass is not as good as the Sony's.
3. VSonic GR07 BE. This I wanted to keep but then changed my mind because of the incident of the ear tips. Good detailed sound with amazing comfort and cable.
4. Shure 215-K. Good with extremely forward mids to my ears. its also uncomfortable and the cable is heavy.
5. VModa-M100. The sound is just extremely bad for a $300 headphones. it lacks detail and the bass I found it to be bad.
6. Audio Technica CKS77. I didnt like the sound of it all and its not comfortable.
7. Westone 3. The worst headphones ever. Mids are way too recessed and its extremely bright to my ears that I couldnt listen to it more than 5 minutes,
The Sony is the best sound ever and I will return it because I hope the XBA-H2 or the XBA-H3 will have the same sound quality with better cable.