As Naomi says not much to add to what has been said.
I would just like to add something which is perhaps a bit anecdotal. An example is given of a corpus lesson in both formats. Because I am really, really interested in corpus linguistics, it did not matter at all to me how the information was presented; I was much more focused on what I was being told.
I would say I prefer Storyline but as I think has been commented in the posts, it is probably a matter of learner preferences; if the intrinsic motivation is there, the information will presumably be assimilated effectively whichever format is chosen.
Storyline seems a bit more interactive to me e.g. I don’t think you can write in boxes easily on articulate, but that is about all I noticed. And the avatar David seems to be guiding me through it more interactively than is the case with the quotes on articulate. Maybe I just need someone to hold my hand as I go through the materials; others may not )))