I've had Macs before and then I'd switch back to Windows, or build a computer and run Linux, etc (interestingly the most reliable, best performing machine I ever owned was a Dell). This year though, I ordered an iMac 27 which I plan to use as my main computer for the next five years (that's my plan at least). The problem is that I have a fair amount of back-up and archive material on external drives (~4TB). Is it prudent to format all of these drives for Mac or should I just leave them as NTFS? As stated, this is largely backup material, so, in theory, I would only ever be reading from the drives (and, from what I understand Macs can still read from NTFS drives). While leaving everything in its current format would be the simplest, a part of me says I should jump in and reformat everything for the Mac system. I am slightly concerned if this would be wise... I suppose I'm questioning how committed I am to the Mac ecosystem at this point. So what would you, more experienced, Mac users recommend, should I: convert all my data for Mac, leave it all in NTFS and then transfer material over to my Mac as needed or should I do some kind of split based on likelihood of usage? Should I jump into the Mac ecosystem or leave a foot planted in the Windows world? I'm a bit torn about this; could use some experienced advice.