Funny, that you ask, because last week i was not shure, which microSD i should buy (used one with 200GB, net 183, is full): the 400GB Sandisk ultra fast with fastest read/write presented in photo- for 130 or the sandiisk ultra 512GB for 44 hangig between all other usb-sticks in computer-department.
To make it short, took the latter and after inserting, mkfs and 5min later: voila, 480GB are shown in df and are now filled near half with migrated stuff.
I need to say, that i'm taking frequently backups of SD, because i don't know, how much rear-mem is on card reserved for bad blocks.