Not sure about the Q-Jays but I like thme better thna the X10 and IMO it has a better hig hfreq extension, I have never ehard the Stax, but they seem to be a little bulky, not sure how is the fit neither...
Also the original Images had a problem in the black boots, as we know, they tend to rip out, not sure but this X5 have not shown that problem till now, so maybe they solved it in the X5...