no i i'm not a fan, but ou're right, very tough to tell on this one. He is so erratic. I would lean towards authentic, but why purchase this "guess" of a signature, when there are more common style signatures from him avail at reasonable prices?
Here is a picture of the 3 CDs that I got signed by Ben in Stockholm. As you can see his signature differ quite a bit even being signed right after each othere. I hope you will find a nice and genuine one.