Well, for the price if you buy them as a package, the 2 games are worth the price.
I know you 1st need to update Mii Plaza to version 4.x, then the 2 new games are available to purchase, so the are seperate
I like how the added the "R" button to fast forward, so you can choose "L" or "R", but it's not for the older games i think
Battleground Z is kinda cool, you fight zombies (Defend the hospital door reminds me on plant vs zombies, there's a level where you need to find 4 tires for a cabbie in a time frame, etc...)
Streetpass visitors when encountered give you different weapons and everey level is another mission, yes i like this game over all the others and Ultimate Angler is just another fishing game
, but all depends on what bait the visitors give you and the also help you catch a strong big fish. Your goal is to get huge mysterious monster fish and every island's fishground has 1 before you can go to the next island.
After all the other streepass games, it's nice to see some new ones and the take a bit longer to play as all the others.
Another nice feature is, to lock-up older streepass games you don't play in a vault (or streepass games you finished everything) , the won't show up anymore then (Like the flower game i never played and that police games.