I have 35 around and it's decent enough for you not to be seen BUT it isn't dark enough. You can tell it's tinted and at the same time it isn't a pain to deal with when backing up or parallel parking. My driver's window is tinted at 50% and I hate it, but having VA plates equals having to tint to VA specs... which is why I might reregister the car somewhere else.
Here's a pic. I know it's not the tint bracket the op wants but to give an idea for tint percentages.
This is right after I got the job done.
