Whenever I throw out to the trash any electronic equipment sitting in my attic, sooner more than later is that I will need that equipment. It's Murphy's law.
You should also electrically fix your VAr, i'm not fresh with my electronics knowledge but VAr (Volt-Ampers Reactive) has no effect electrically on equipment (those are waste) because you are billed by the resultant vector of the sum of Watts (work) + VAr (Waste) = Tariff Bill
About your monitoring command:
lsof -w /mnt/* | grep /mnt/ | wc -l
Have you taken a look into incrontab, maybe it's more cpu efficient, but i don't know, so you could take a look into it.