Pros
FNC is a market leader in optical transport in the US. There is some flexibility in work hours which helps with work/life balance. An on-site gym is popular at lunchtime. FNCs largest customers are AT&T and Verizon so it has a strong customer base for its current prodcut generation.
Cons
Employees are siloed - they toil away in the dark and have little opportunity for any real recognition. You won't get rich at FNC. Upper management is isolated. There is a Japanese expat clique that keeps to themselves. US managers only talk to each other. You won't see them walking around the building talking with anyone. The real decisions are made in Japan - HW development is there too. Japan develops the products and dumps them on FNC to sell in the US. You are only provided with the information you absolutely need to have - knowledge is power so people don't freely share information. The company has a vested interest in laying you off before 5 years - before you vest in your 401K cause they keep the unvested funds when they get rid of you.