Soundwave on 27 February 2015
Wouldn't make a huge difference for me. I haven't found a game that really enhanced the game play of any Wii U title too much, but I don't have Zombi U either (wasn't crazy about the demo though).
As for off-screen TV play I find it mostly pointless too. We waited 6 years for Nintendo to go HD, now that they have, playing the games on a low-res, crappy 6-inch display when you have a HDTV to play in the same room just seems like a pointless endeavor.
The only thing I like about the Wii U tablet screen is the lower resolution/crappier quality actually looks good for SNES games ... they look how I remembered them (ie: Donkey Kong Country), whereas on the bigger HDTV they can look really dated.
