Pros
The client base is generally pretty agreeable, which is hard to find in this industry. It's actually rare to hear people demand ridiculous things, which makes the job pretty smooth. The work is exactly what you expect in production design, and you don't have to worry about customers wandering into your working space.
Cons
FastSigns are individually managed, so you can run into some interesting management styles, to be sure. I started working there at a weird time, so things were more hectic than they had to be, in my opinion. But, I don't know very much about managing a branch of a company and I know my previous boss had a lot on their plate. That being said, work environments and the pay can really make or break your experience. There was a lot of rush work and crunch, to the point where I stayed overtime once or twice a week. There's a lot of work to be done. If that's your speed, then more power to you.