5 star for sure. Got dropped off by Bolt at the front step, walked in. Information board at the…read morefront. Very easy to navigate. 1st floor has several restaurant to grab food, gift shops and also rest area. Next to the rest area has OBB dedicated rest area. Near the exit, there is OBB office to buy tickets or make changes.
Information board os accurate and large signes directing you to the upstairs platform. You can also take the escalator next to the stairs. Must if you have a large luggage.
On the screen, if the white circle blinks, that means your train has arrived and you can board.
All OBB seats can be reserved for few extra €. If not, just seat at any open seats but expect to let it go for people with reservation.
Definitely 5 star station. There are few very busy, dirty and unorganized trains in Europe especially ones in Zurich.
Watch out for pan handlers.