Chris, I've also suffered from freezes (about once ever 3-4 days)
ever since I've moved to GuixSD.  But I haven't tried any other
distribution in the meantime, so maybe it's a kernel issue.

I use a custom kernel although I'm not sure if this has anything to do
with it.  I've tried various Linux kernels in the 4.14, 4.15 and 4.16
lines.

I have noticed some issues with my discrete Nvidia card (which I don't
use), maybe it has something to do with it.

--
Pierre Neidhardt