Pros
The pay is really good for retail. Working in cosmetics is a lot of fun - you get to play with makeup every day! You are responsible for making your hourly numbers, thereby ensuring your current rate of pay (or ability for a raise). The Dillard's I worked for was full of friendly people, and our store manager was really great. The opportunity for upward mobility is definitely there if you're willing to work hard.
Cons
Because your pay is based on making and improving your sales goals, your pay can be cut. If you work for a cosmetics counter within Dillards, expect to have your company responsibilities and requirements often to be at odds with what Dillard's expects you to be doing. For example, your company may want you to be promoting a certain product, complete with marketing material for said product, but Dillard's may be promoting something completely different, or even a different counter's (your competition) promotion. I've worked for 3 separate department stores as a counter manager for a cosmetics company, and Dillard's is by far the worst/weirdest when it comes to working "together" with your competition in the other counters. Because the focus at Dillard's is on making your own personal sale's goal, things in the cosmetics department often become cutthroat/catty, with people doing anything they can to make a sale, even if it's not their department, or they don't know what they're talking about.