Awesome!   bendjude   I'd love to see some more Grado products and maybe some phono cartridges eventually

Forgive me I'm a bit new to all this but I'm looking to get a portable amp/DAC to use for my headphones, I've got a pair of the AKG K553 Pro and mainly use them with my windows laptop but also frequently use them with my Ipad Air 2 and Samsung Galaxy S4. I was looking at the FiiO E12, E17K, or...