How does Disk Drill Pro compare to TechTool Pro for disk maintenance/recovery? Thanks to good backup strategies I haven't had the need for anything like that yet, but I already have Disk Drill Pro purchased and installed on my Mac (part of a software bundle) though I've barely tried it out. Still, I hear that once an incident happens it's good to have an arsenal of tools around. Disk Warrior is on top of my wishlist, but appears never to be discounted. TechTool Pro however is currently discounted 60% for the next 2 or 3 days at Macnn and TwoDollarTuesday and I'm wondering if it's worth getting or if I already have what I need in Disk Drill Pro?