One thing that bothers us a bit about Brain Age and its sequel is the daily-play design. Sometimes we like that we can fit a satisfying gaming experience into just a few minutes, but sometimes we have two hours to kill playing games, and we want to play Brain Age. While you can train all you want, you can only make so much "progress" in one day, due to artificial constraints. If one can even be said to make progress in a nontraditional game like Brain Age, that is.
What about you? Do you like it when games feed you pre-measured portions of game time? Or do you really hate running out of stuff to do?