You don't need to use either one. There is no reason to backup your nand on vwii, unless you have some need for those files to modify and such. It does not help prevent or fix bricks. What you do need is your nand keys, which you can dump with xyzzy. There is a modified version of xyzzy that uses ahbprot which will work with vwii. Don't use pimp my wii. You are welcome to dump your nand with fstoolbox, there is also a modified version for vwii, but it will not help to prevent or recover from a brick.