Originally Posted By R. Belmont
Actually, you'd want to save state for all devices currently present, and then ignore the data for devices that aren't present when you re-load. That has the best chance of keeping save states working for debugging. (And not coincidentally, it's how many PC games that support user mods work for saving the game).

Currently, state is not associated to devices, and worse post-load callbacks aren't either. I have a patch locally that adds the link, which shows that a lot of state is not registered associated to the device somehow. We'd have to clean that up hard.