I had been working in this kind of company before. It was stressful and you cannot talk personal phone in the office, you cannot ask colleagues if you don't know how to do except your boss, you had to sign-in and sign-out if you go to toilet, etc. However, they will give you extra $500 bonus per month if you had not been late for the whole month (both arrive office in the morning and during lunch time).
I left within a month because I was not happy and I could not learn a lot because my boss was always busy and not really willing to teach me.