Smooshy mice are ok. I guess if the Hampers say it's ok to leave it out all day, then maybe it is. But I wouldn't do that. If you want to be sure it's thawed completely, do the same thing they said, but put it in the fridge for the day...then just warm it up before serving. You should warm a room-temp mouse anyhow. I leave mine in the fridge overnight, the night before I plan to feed. (Or at least I try to, sometimes I forget! LOL)