Bit of an OCD question, I admit I use OnyX and Disk Utility to Verify/Repair Permissions, clean Cache etc and to generally look after my Mac. I also make sure I sleep it whenever I can so it can look after itself. BUT... I have two external drives- one for storage and one for Time Machine- any point in running Disk Utility on these just for super safety? Also, would there be any performance gains? Just anything that would extend the life of my external drives would be a bonus. Or am I just bored on a Sunday night looking for something to do...?