It's okay when you're starting
Pros
They give you dedicated training in your first 5 months. You learn Japanese and the company's culture (which is heavily influenced by Japanese culture and work ethics) They also give big bonuses at the end of the year and they try to be extravagant on outings and parties...I mean, if you could join those.
Cons
It is heavily influenced with Japanese work ethics (yes, there are several cons to that, including overtime for hours on end). Messy project handling. Since they adhere strictly to Japanese culture, you are expected to do EVERYTHING even when the fault lies in the client's error (the idea is that you fix your mistakes, you fix their mistakes). This is not really true to all clients but only the ones with...poor communication channels. Some clients are reasonable while others...especially those from the older generation basically still adheres to the "Dedication is to die working hard" ideology from post-WW2 mindset. In relation to above, OT pay or basic salary will never be enough. In fact, time will can never paid with money at all when you realize you've spent around 18-20 hrs at work (even more than 24 hrs in some projects) per day EVERYDAY. Oh and people aren't lazy, mind you. It's just that majority of the clients treat you like adhocs always on call, or that they change requirements far too often (there's no locking contract), or that the clients themselves make a huge mess that you are expected to clean up--even when it's outside of the agreement. But again, it's only never enough because of the suffocating work ethics that backfires on the employees of the above reasons. Otherwise it would have been sufficient if you're just starting out in the industry.