I haven't heard either of the IEMs you listed. What do you like about each one? Do you need them to be closed/open for isolation reasons? Do they need to have portability? Are you willing to purchase an amp? If you can answer these it might give a better idea of what headphones might work for.
The GR-07 is very crisp and clear, but not fatiguing with continued use. What it lacks in bass I am able to accomodate for using the E17. The EPH-100 has a nice, wide soundstage with more depth. I switch back and forth between both quite frequently.
I am actually able to increase my budget more now, into the $400 range. As I said my taste is all over the board. I can listen to classical music, an instrumental piece from a soundtrack, techno, Metallica, Bon Jovi or something harder like Skillet or Seether. I dont need to be sitting front stage when listening to music, but I do prefer depth, crisp vocals, tight mid-bass and little to no sibilance.
I prefer over the ear and comfort is important. I prefer closed for isolation so I dont bug the wife too much. I am hoping to go with something that can be driven by the E17 for the time being, but a new amp down the road will be a possibility.
I originally started out looking at the M50's due to the hype, but started looking elsewhere as I read more and more threads. I have found a good price on the Ultrasone Pro 900's within my budget and was looking into them.