Good feedback. I have been focused on portable amps lately now that I am situated with headphones and the only portable amp I have found with more power is the Centrance M8 which offers charging, DAC and lots of bells and whistles, but is also 3X the size of the E12 and 5X the price.
Honestly man, for the price of the E12, you'd be hard pressed to find a better sounding amp. Admittedly, I have only heard a few and I am relatively new to the audiophile world (I consider myself to be an enthusiast, not an audiophile), but I've been working in home and commercial audio for 15 years and I know what sounds good. The E12 definitely sounds good, and I am honestly blown away at just how good it sounds. I just did an A/B between my iPhone 5 on its own and my iPod classic w/ the E12 and the difference in sound quality is staggering. The very first thing I noticed is the enhanced soundstage and imaging, followed by a warmth and sparkle that you just don't get out of the iPhone when listening direct. A lot of people here seem to steer clear of products with warm signatures, but I love them and I think the warmth brings out the musicality in... well, the music haha. Without the bass boost the sound is definitely more neutral but that boost just fills the sound out perfectly for me (I am NOT a basshead, keep in mind). Even my mother who thinks Sirius radio sounds good was able to hear the difference between the unamped iPhone 5 and my classic/E12 setup. I can't think of any purchase in recent memory that I was this happy with. $130 VERY well spent. Good show, Fiio.