Pretty hard to say, depends on your speed and how you have it set up.
And you don't have to set it on top of your headlight, you can raise it up a bit.
Having said that, what do you want out of your shield?
for me, southern California, I need air, lot's of it.
shoot the a/c don't work below 70 as is.
but no shield leases me battered and bruised.
I love my flyshield, plenty of air, yet the worst of it is off me.
it's a short screen, off the top of every shield is turbulence.
it's pretty thin... mine hits me at the shoulders... keep the turbulence off your helmet though or you'll feel like a bobble head doll.
BTW... plenty of advice on the subject... use search for windshield, change timeframe to all.