I don't have the 16, I have the 13, but I've been impressed. [The slots would be cooler if they were hot swappable, but it's generally not been an issue.] - Holy shit I can hot swap. Ignore this. Other points stand ;)

Build quality has been good, it survives being chucked in and out of my backpack and it's survived a drop off a bar stool to hard tile.

I really hope they keep iterating and improving, there's certainly things that could be better, but they're on to something in my opinion.