Do it yourself TarDisk?
A few years ago, I added a 256 MicroSD card with an eBay adapter to my MBA SD port and I wasn't impressed. It was incredibly slow and I was constantly getting the beach ball. Now I'm hearing about these TarDisks and I'm wondering how much of it marketing hype.
Even at UHS‑I speeds, $400 for a 256GB SD card, is highway robbery. Is there a do it yourself solution that's comparable to TarDisk? The software just joins two partitions together, right?