Hey everyone, haven't seen alot of information on here about the Etymotic Research ER6i's so I figured I'd write a little "first impression" review. I got these yesterday and have allowed them to break in for about 24 hours (a little less). While I'm impressed with their resolution on single instruments, when there are more than 2 or 3 layers, they really struggle. They "break up" and really strain to reproduce midrange sounds, especially at the lower end of the spectrum. I'm thinking I might send these back to Amazon for a refund, but want to give them a little more time. Anyone know if the hf5 would be a pretty big upgrade over these and probably resolve the issues I'm finding?