Got a pair of these a few weeks ago after returning my defective pair of FXT90s and.....DAMN! I didn't know sub-bass existed like this! And the rest of the sound....I listen to tracks now just to hear stuff I never heard before. From what I've had previously, they isolate really well. I have to tell people to wave or throw something at me to get my attention, because I won't notice them yelling at me. Speaking of not noticing, after I figured out the fit, they simply disappear! I barely feel them. These are a really well design pair of IEMs that really deserve more attention.
As a result of this experience, I've started letting everyone know just how worth it is to get a good pair of earphones. I get a huge kick out of letting people trying these and just watching the smiles on their faces. They, without fail, say they hear things they've never heard before. In fact, several of them, my girlfriend included, are seriously considering buying a pair. These are people who would have never considered spending this much on a pair of headphones.
In any case, I want to thank the Head-Fi community, especially Joker, for recommending these. I would not have chosen them without you guys.