I've had many more problems with AA in the past. (Like Styling, simple_form) I quite speedily dropped AA in favor of building my own AA backend, which is not that hard... AA consists out of a lot of stuff that you can just as easily put in your Gemfile. like inherited_resources, has_scope, devise, cancan, kaminari in favor of AA's will_paginate, and ransack.

I'm currently happy not to be on AA, it seems it would have held a lot of development back. AA ties you down to a lot of stuff that might break in the future. I think it's a great gem if you're starting with rails or need a quick admin backend of your models (when your site is mostly frontend). If you're looking for a true backend that needs some degree of custimization I woudn't risk it.