Note: the (slower) part is an addition from Tom, though nothing bad intended nor taken from that.

Looking at the earlier posts in this thread, storage concerns seem primarily for media -- photos and video. And the SD-Cards are plenty large enough (200GByte and counting), and more than fast enough (by an order of magnitude) for such purposes. So yeah, slower than the built-in "SSD" style flash, but still way (up to 12X) faster than the 7MByte/sec for 4K video needs.

I just wish Google would include a slot for them on their Nexus devices. But even Apple is more likely than Google on that front.

Cheers