$492 for 256GB? I'll pass for now.
We could already go for the ZIF instead and pay $300 (or less) at the moment. KingSpec from China probably sucks but that's only 1,439 RMB / 240 bucks plus shipping for 256GB.
Actually I've been using a kingspec 128 gig in my old iriver 120 (too big for daily use now) and it's fine. Rockbox works on it as well.