Heres the problem you're going to run into. Count on it.I am in the process (yeah I know) of setting up my WiiU 5.1.1, I did buy a DS game before so I better get to it. I think RedNAND is great for the following reasons:
- NAND has only so many write cycles. The WiiU apparently writes to NAND often (log/activity files etc.). A RedNAND takes the burden off the built-in NAND and can be backed up and replaced easily.
- If you mess something up badly, restore your last backup and don't make the same mistake... brick-proofing your WiiU
- If you're in RedNAND and somehow there's an update, it can only stealth-update RedNAND, SysNAND is fine
- Given enough time, you will probably have the same as 3DS right now: use an out-of-region EmuNAND to get 100% compatibility
On the 3DS I had a 9.2 SysNAND and higher EmuNAND for ages (until A9LH/B9S with Luma which made EmuNAND unnecessary). I'd say that until we have super-early code execution on Wii U, a RedNAND is still a valid option.
You'd better back up redNAND often. It's prone to corruption. You think your SD can handle all the writes that the built in nand Can? You're mistaken.
If you're a power user and you don't mind constantly taking your SD out to restore your corrupt emunand then go for it. You'll be safe but you'll be busy too.