A) Sort of. I have a SanDisk 512GB SDXC card, and it formats correctly. But the iPod's iTunesDB library is limited to 35000 songs. So for most people, there's n

A) Sort of. I have a SanDisk 512GB SDXC card, and it formats correctly. But the iPod's iTunesDB library is limited to 35000 songs. So for most people, there's no point in having more than 128GB. Rockbox is not my music player, because I want my play counts to sync back to iTunes. I still want more capacity, but see my explanation in D) WiFi. B) Weight is not an issue for me (I started with a 1G in February 2002 - everything else seems light). C) Battery life is longer with SD cards than hard drives, but that's not a big issue for me. Sync speed is also faster, which is a small bonus. D). WiFi is the big feature that put the iPod back in my pocket. (It was gone from October 2011 when I got a 64GB iPhone 4S until March 2015). My iPhone's got a lot of space, but 10GB of Wiki2Touch (offline Wikipedia), 2GB of Galileo Offline Maps take a toll, before I even start to sync my 85GB main music library (my external library is over 300GB, but it isn't duplicate-sorted; it's the backups from friends' iPods). When I had an old iBook with a 10GB hard drive, and a 30GB iPod, I backed up my entire disk to my pocket. That was awesome. If my bag were stolen, I'd lose my laptop and external hard drive but not my pocket-sized backup. Now I have a lot more data, and I want to access it from my phone. The 512GB SDXC lets me backup my laptop. The PQI Air Card only supports microSD, but I use an SD female to microSD male ribbon cable adaptor. Power to the card comes from the iPod through the iFlash. My "WiPod" is therefore effectively an AirStash (SD to WiFi) and iPod in one. It's also useful for copying photos from friends' cameras. During many of my iPod-less days, I had a Raspberry Pi in an iPod shell in the belt clip case. That had host USB, so I could also mount iPhones using libimobiledevice and copy music from friends. Most of the time I just used it for photos, though. I'm still trying to find a way to get host USB into my iPod, though. The CoreWind WiFiG25 is my current favourite (it's small enough to fit in the iPod's case). But CoreWind still didn't finish the WiFi driver for Debian. If backup is so important, why didn't I use mSata for 1TB instead of 512GB? Because I only have 512GB of data, and accessing the files is as important as carrying them. Everybody uses SD, and sharing over WiFi to my phone is super useful. And I can backup my laptop to the SD card (only 2 USB ports) while my iPhone and mouse are plugged in.