+1 from me for both mount-observe and hardware-observe. This seems appropriate for an application which has a primary case of reading/writing to disks to benchmark and understand the hardware.
Apologies, this request seems to have slipped our radar and went completely unnoticed by the reviewers team - +1 from me too, these are both clearly required for the standard functions of the snap.
+2 votes for, 0 votes against, granting auto-connect of mount-observe and hardware-observe for kdiskmark. This is now live.