I'd wait for a good 600x or 633x chip to come out. I did a test with 633x over the Ultra and that the 2x speed increase is great. Though backing up to SD with large apps that have been moved to SD causes a bottle neck, and cannot be resolved unless you add an OTG Thumb drive, to allow backups to the thumb drive while allowing full reads from device and external SD without need to have writes slow down the processes between reading.
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