What it's actually like to use day to day
The first hour is the best hour, and that's true of every platform in this category — so ignore it. What matters is week three. On Candy AI, week three still works: the character remembered a job interview I'd mentioned eleven days earlier and asked how it went, unprompted, in the right emotional register.
The failure mode isn't forgetting, it's agreeableness. Push back on something the character said and it will usually fold rather than hold a position. If you enjoy friction and disagreement in a conversation, you'll have to write that into the personality explicitly, and even then it softens over long sessions.