Pros
I loved the team I worked with. My co-workers were super nice, helpful, and my project manager (not a Frontier employee) was always working to keep everyone involved, and was quick to address concerns and projects. Benefits were good, and so was the pay. I enjoyed my work life balance, and my team was great.
Cons
The position I was offered was not the position I was given, and I still had to take it, due to having turned down other prospects. Poor allocation of human skill sets to do jobs. Contractors also have the fun experience of essentially doing the job of a staff scientist without the option of being able to be hired as one.
If you're looking here to start your career, you're better off looking directly at the main company Frontier contracts people to, and trying to get a staff scientist position. If you're planning to only stay for a year or two, then this isn't a bad place to work.