Re: Small amount of space left after wipe.
Damn. I totally mis-read your original post.
Yes, yes, the little bit of space is normal and expected. Windows creates files which we cannot see in the System Volume Information folder. It's locked up, and unless you do some Windows wizardry, you won't be able to see the contents of the folder. The system keeps persistent volume information there. That usually accounts for the space taken up.
Also, other NTFS file system data files use up the available space, which Windows does not expose to even other programs.