How is Tozai line at around 9am or 9:30am from Takadanobaba direction to Otemachi?

I am looking for apartment right now. Really love the area around Waseda and Kagurazaka. However, I would need to commute to work using Tozai line. Since I can afford to leave later, I would like to ask if the Tozai line gets better at 9 or 9:30 am. Thank you!