I've owned a pair since 1998 - and still love them...although I do have considerations about using them at home.
First off, I've had one bout of swimmer's ear (an ear canal infection) that forced me to not use them for about 6 months; secondly, I often can't hear the phone when they're inserted and have music playing through them - so they can be impractical in certain circumstances (if also ideal when using meditation CDs!), and repeatedly having to pull one out and then reinsert it can lead to wear & tear on the inner ear.
Hence, I've been looking for an over-the-ear phone with the same degree of detail & immediacy as the ER-4S provide. I'm leaning towards the BeyerDynamic DT-880s 600s. I have an older pair of 990 600s (of 1993 vintage) - and they don't sound nearly as immediate and detailed as do the Etymotics - but I've never had them properly amped (still using a Headsave Classic that Norm built for me about seven years ago, which I'm sure isn't ideal).
Any suggestions on a full size phone that sounds like the ER-4S?
Thanks in advance.