I like how it's very customizable to fit your needs; there are so many options for different types of galleries! The customer service can be somewhat hit or miss sometimes but they're always quick about responding when we need help/support via email (even at 3am).
It would definitely benefit from more tutorials available online if someone new were looking into this program as well because not everyone knows what all these features do by default in their installation files. We use AB primarily out-of-office hours where our clients aren't around us during normal business days - great way to have access even then without needing physical presence anywhere near them.