I believe they are both classified as micro fleece, but they are different in feel and texture. The Ayton is 300 weight and the Rut is 335 weight also.
I personally like the feel, texture and softness of the Ayton better. I believe the Rut will be more durable however.
I heard from UA that the Ayton series is being redesigned for this year and some stores are already running out of stock on the current design. If you want the current Ayton you better snatch them up while they last.