My sister has a DS with brain training 1. My fiancee has just got a DS but has heard 2 is better than 1. Will they still be able to play against each other with different versions of the same game or do you have to match 1 and 1 and 2 and 2?
You don't need both carts. It's all done via Download Play, where one DS has the cart and the game is shared over WiFi. So, you only need one of each. More Brain Training isn't that much better than Brain Training, just sort of like the same sort of tasks, just a few differences to keep it fresh.
Got this a little late so have both BT now, but the download play is a good idea for some of the other games Thanks for the advice.
http://www.nintendo.com/dsdownloadstation/#howto Do you need to download anything from the web first or just have 2 DS in proximity and play from there?