This is great and gives Slides the same functionality that PowerPoint has to make 1-photo per slide presentation from a set of photos. Saves me so much time. As far as the functionality, its 4 stars. Some photos albums show up as "unknown" on the drop down, luckily not the album I needed.
I really don't like the expansive permissions like others have said here. It's major. So, 2 stars until that is fixed. I did pay the $2.50.