Pros
The culture is relatively genuine - what you see is what you get from people, and that makes people generally pleasant to work with. If you have no aspiration but to remain safely employed with an average salary, this is a good place to be. Lunch is free and very good. There's a decent gym, too. If you're a Korean male, this is a great place to work. It's like 19th c. colonialism - if you're a low-level Korean, you can abuse and order around any non-Korean and there's nothing anyone can do about it. The work-life balance is inconsistent - it depends on who you report to. I'm fairly lucky in that regard - but overall, probably better than average for a Silicon Valley company.
Cons
SSI is an impossible place for high performers. You have no decision-making power, the company is parsimonious to be point of ridiculousness, and all decisions are made in Korea - slowly, and almost always "no." The president can only approve up to $500K in capital expenditure, so nothing can ever happen unless it's an initiative from Korea. High performers stay long enough to get some experience and then flee the stifling atmosphere for more dynamic companies where they can spread their wings and get paid reasonably. Your highest level unless you're Korean is Senior Director, except for a handful of positions that require cultural familiarity like HR and Sales & Marketing. The culture is race-based and very difficult for women. The HQ is the greyest, most depressing place I've ever worked in, with nothing but row after row of ice-tray clusters of cubicles. It looks like something out of a dystopian film set in the 1990s.