Snagged an E12 about a week ago from Headfoneshop Toronto.
Absolutely love the unit.
I am going to try coating the side of the amp closest to my phone with high quality 3M EMI Shielding tape to try and reduce EMI from 3G/LTE/Wifi. Using Airplane Mode until I can get my hands on it. Will let you guys know how it goes.
Setup is iPhone 5 -> official Lightning to 30 pin adapter -> Fiio L9 cable -> E12 -> Ultrasone Pro 900
Low gain, no crossfeed, no bass boost (well on some dubstep tracks I turn it on). I commute about 4 hours a day and listen to music throughout that time, and 30-45 minutes at work. I have yet to charge it in 3 days and the battery warning light has yet to show.
Build quality is excellent.
Edited by Scorpion667 - 1/21/14 at 3:17pm