Apologies if this is possible already, I haven't found it (yet?).
From my limited experience, the models remain safely on the raft, but the raft may in turn lose contact to the printbed.
I've noticed that the raft seems to be only a bit wider than the width of the model. Which means that with models that are printed standing up, the raft isn't really providing that much grounding.
Which is why I'd like to make the raft bigger, in the hope of getting more stability.
(Probably someone already thought of this? If so, even if going off-topic, I'd love to read the reason why it wouldn't work. It seems good in my head )