I would strongly suggest you check your state law and go no darker than what your state law is. Otherwise, you run the risk of being stopped and either ripping off your tint right there or get a ticket. Here in Kansas the limit is 35%. Always best not to give the police any reason to stop you. Who knows what you might smell, see or plant in your car. Not to mention if you get into an accident at night, the other party could easily claim your tint was too dark to see and thus you are responsible for the accident.
I just got a 2022 RX350 and will be tinting to 35% tomorrow.