Since there is no equivalent to EmuNAND from 3DS to let you buy DLC and eShop games while having the hackable older version, are the hacking features you get from having an older firmware version worth losing the online functionality?
Can I at least back up the NAND somehow so that I can go back to 4.1.0U if I want?You can hack vWii (basically the same as a regular Wii except a few files are not interchangable without bricking), but not the full Wii U mode.
As for the full Wii U mode, we're not sure if its worth while.
Can I at least back up the NAND somehow so that I can go back to 4.1.0U if I want?