That doesn't make sense. If the drive was "formatted for PC only" that means it was likely NTFS or FAT32. You didn't need to use another computer to transfer files to the Mac, as OS X can read and copy from both formats natively. You can install Paragon on the Mac to read/write on NTFS drives from OS X, completely eliminating the need to reformat the drive.
The drive was formatted NTFS. I tried to drag and drop the files from the external HD to the mac and it didn't allow me too. I had important files, family photos, etc. in my external HD that I didn't want to risk loosing, besides I had no way of backing them up, because I switched over to mac, so I did it the long way. I'm just glad I got it done. It took almost a full day, because I was maxed out at 500GB of files.
Had I known about Paragon, I would have used it. I posted about all this a while back and I don't recall anyone suggesting Paragon as an app to help with this issue. Thank though; now I know.
EDIT: I stand corrected. Your above post looks very familiar. You may have replied. I don't think I wanted to spend the $19.95 for Paragon.