The thing that get's me is why we signed him in the first place as I get the vibe Warne would preferably play 3-5-2. Unless we consistently start playing something like 3-4-3 / 4-3-3 etc, he's not going to get a regular run in the team to build confidence / form.
So at the moment it's hard to fairly judge him, but I also question the logic of buying him (and the same would go for someone like Dembele if that comes to pass) unless we regularly play 3 up top. If we do play that way and play him on the left wing, as others have mentioned, then let's judge him after a decent run in the team.