I have had Klipsch x10i's for a little over a year now, they are for sure my favorite IEM, I have tried Etymotic mc3 and HF3 which I did not like at all because of the lack of bass, however now my taste in music has completely changed and I prefer a flat accurate frequency response over the slanted V on the equalizer, I haven't tried too many high end IEM's but a lot of low and mid range iem's so I am sure people would choose something different then the Klipsch x10's but I choose them because of their comfort, I sleep with them every night, they sound great unamped with every genre I have heard, especially Jazz & Classical, wow.. I would never spent 350$ on these mostly because I got them for free...
I have seen the x10's going for 199.99 which seems more reasonable, but I still would have a hard time spending that much on an iem, I spent 180 on my Sennheiser HD 558's and that was a lot to me, probably because I am just working part time right now with a ton of bills.. I got my x10i's for free from Klipsch because I posted a review on their website about the s4 & s4i's build quality how they fall apart and I went through so many pairs on warranty so I get an email from a Klipsch rep saying he wants to mail me a pair of x10i's to make it up to me, I thought it was fake but I gave my address and and name anyway figuring that's all he's asking for, whatever.. I receive a pair in the mail a week later shocked and blown away..