FSI
I worked for FlightSafety Academy eleven years ago, which may not be the type of FSI in which you're interested. I can tell you, though, that the company offers decent benies, i.e. good health and a 401-K.
Our Center had very poor morale. I feel it had a lot to do with the managers. They weren't entirely honest and consistent regarding pay, and treated people with little respect. I think that was because so many instructors were young people. Most had trained there and were short in the maturity departmen. Also, they weren't staying, so the management had no vested interest in treating them right. Other centers may be better because they want and attract mature people.
I recall meeting someone at the Bethany, Oklahoma, Rockwell Commander FSI Center about sixteen years ago. He seemed like a decent enough guy, if that is any indication. I also spoke by phone with someone at the Wichita center, and he seemed to be okay as well.
Hope that helps. Good luck with your efforts.