Off-contract, injuries affecting the forward pack, he's a big attacking weapon who loves to offload and break tackles and the Storm's early draw is really good (Eels, Dogs, Titans, Tigers are their first 4).
Given Kamikamica's injury (and Kami would get 45-50 mins a game off the bench) and the departure of Cheese, NAS seems nailed on for 50 mins a game and has a lot of attacking upside that other MIDs at his price don't.
Obviously there is some risk to picking NAS, but it could pay off big time