TheDreamthinker
Headphoneus Supremus
If you're not a part of the Apple ecosystem why get into it just for larger capacity? And through that expensive method, instead of for example an iPod Touch with a 500gb Seagate wireless drive?* The Fiio X5 can take two microSD cards, and AFAIK, it can do two 128gb cards, but there's a certain limit on the number of tracks - which I doubt would be an issue if you loaded it with lossless anyway. If you're using 320kbps, but still need that much storage, then just get used to swapping out microSD cards - back in my day (you know you're getting old when you start making a point with that) I had five MiniDiscs in my schoolbag, plus one in the player, and each of them has only one album.
Note that even some iPods slow down on a full drive with lots of smaller files, especially if it's much bigger than what that version came out with.
*During the 4g and 5g iPod era, some people just bought a second or even a third iPod if they were using ALAC, then fill one up with one general genre - like jazz in one, classical in another, rock in the third
As I am currently already using an iPod (and therefore iTunes), the ecosystem won't be a big problem...
I have experienced SD cards to be unreliable on several occasions...and 128GB cards have not yet reached a price point where buying 4 is really an option.
I have already looked into the Seagate Wireless Drive, quite compelling yet slightly unpractical and expensive. I also already killed 3 HDs by carrying them around to much - life of a frequent traveler.
Thanks for the input...