I'm using MOG Artist Radio through both an SB2 and SB Radio -- though the exact menu options are different, both devices give the ability to select from a list of diversity choices, from the selected artist only to only similar artists.

However, as far I can tell, these choices make no difference. In all cases, I get approximately 90% tracks by the selected artist and 10% from others.

(Using the MOG web UI, this works exactly as I'd want with the same artists -- ie, I can really change the mix in several increments from all songs by the artist in question to all songs by related artists.)

Can anyone else confirm that they see this same behavior?