Pretty sure I already answered this, look back a few pages. I think I suggested looking into H2O Audio, waiting for the Sonys, and maybe the MEE S6s. If you need sweat resistance, there's not a ton of options in the high end.
I would recommend checking out ljokerl's review thread for more options, as he's reviewed both the S4s and the iBeats, and ranks IEMs on a consistent numerical scale. It's really a labor of love, and it would be terrible if you didn't at least give it a look. Check the bottom of the page, where the summary chart is.