Thanks for the great review! I am considering this with my new Shure SE425s. The E6 is such an improvement over the amp in the iPod (I use the line out from the dock connector) that it seems like a no-brainer.

I don't have the E5, but I find that the E6, used with most decent (i.e. Shure SE215, SE435, Ety HF-5) canal earphones, simply cleans up the iPod amp 'mud' when used with the "line out" cable that pulls off of the dock connector. I don't use the bass-eq functions because I prefer accurate to...