I've been using large bluecell from Amazon. They've been the best fit out of any iem I've worn. http://www.amazon.com/gp/product/B0081P7T3W/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

After a day of burning in. The bass seems a little mellowed, but still enough. The mids and highs are still on par wth the 400s. The biggest advantage is the fit. The 400 always needed some adjustment to be perfect. These stay put. The cord on these are a little stiff though. I hope that...

I just got the white ones in. eBay guy said the blacks are 16ohm and the white are 32. He's sold out of both. I was going to return them for the blacks, but I'm starting to like the white and the sound is amazing. They sound identical to my re400s with a digizoid. The fit is much better. I threw...