Pros
Benefits, and pay. Educated workforce. Good hours relative to what you expect. You can learn and grow quickly.
Cons
Too many firings, hard to get attached to people because sad seeing friends get cut. Dutch culture is not normal for Aus/NZ raised kids (more so NZ than people growing up in Syd/Melb).
Too much advertisement on how good the firm and culture is. Always good image. Not HFT or hedge fund, its 'market making', and 'we love our women' while having a very boys club trading floor, and HR protection for the senior staff.
For every graduate employee that makes it into high bonuses, another gets casted out into unemployment and mental health issues. Every year the graduate group come in all optimistic, think the cut throat culling of grads is in the past and changed, that everyone will be happy - little do they know everything is a test, being evaluated constantly, and hugely intelligent people get kicked out each year regardless.
But don't worry, you can get paid well and have all the benefits of food and high end perks, but you may very well come out with long term health issues.
You can even find a youtube ad of Optiver back in the day where an old man on a bench gets an errection. That culture is still entrenced.