If you are short, you can look through the stock screen, if you are tall, you can look over the stock screen.
It will be interesting to see if anyone with a Fairbourne screen in the UK fails an MoT test, come the time. Construction & Use regs require that a screen through which the driver has to look needs both a wiper and a demister. We can get away with the fly screens (despite often looking through those myself when it's wet), as it's always possible to look over them. Not so sure about the FC screens in that regard however, particularly for short-ar5es like me
But as usual, it's probably down to the MoT tester at the time.....