A bar chart is only going to be better if the data is inline though, I'll upload the proof of concept I just knocked up for the chart, see what people think as a quick indicator
While I think it looks good and I admire the theme in general I still think bar charts are better suited for this sort of information if the goal is to show usage.
It's "slower" to scan each pie individually than it would be with horizontal bars where you would quickly spot which disks have the most usage and/or free space.
sda - serial - model - |||||||||||||||||||||||||||||
sdb - serial - model - |||||||||||||||
sdc - serial - model - |||||||||||||||||||||
nice work