I just installed Role Scoper and it did exactly what I wanted it to do, and I thank you!
What I did was set a few pages in my blog as editable by the Subscriber users. When I logged into my site as my new user, two very small issues came up.
First, "Add New" exists under the Pages menu. When I click on it, I get a message that I don't have permission to see this page. That is as it should be. But I would rather the "Add New" menu item just not be there if the user is not permitted to add new pages.
Second, when editing a page, I tried to turn off the "Readers" pane using Screen Options, but when I unchecked it, the pane did not disappear, and the next time I opened Screen Options "Readers" was checked again.
Of course, these are very small matters, but since you're in development I thought I'd weigh in.
Thanks so much for a great plugin!