I see a lot of the pros have taken off the original eye shield of the Giro Selector. It seems (but almost certain I will stand corrected) that the eye shield is more aero?
Maybe you would do this to gain better eye protection from better sun glasses? Or maybe just because Oakley pays in gold if you sport their glasses leading into T2?
Tom
Having the shield must be more aero. I’ve removed mine as after transition it steams up and I have 15mins of trying to see through fog before it clears. I’ve tried anti-misting sprays, but nothing seems to stop the shield misting up.
I suspect sunglass sponsorship and/or heat/ventilation. It’s a warm helmet.
Fogging/misting is easily controlled with a little Rain-X anti-fog on both sides of the lense.
My reasoning behind taking off the visor is for improved ventilation (I realise this is an oxymoron when talking about aero helmets).
Good points on ventilation - I am still to try it on a hot day, but already dripping. Had no issues with steam/fog though.
I tried it with glasses, but its so snug, they wont fit 
Have to suffer for aero, right? Cheers
When it comes to the aerodynamics of the visor, I think you are splitting hairs. I typically use the visor for olympic distance and cool 70.3’s because the visor offers better visibility in my position. For warmer 70.3’s and above (anything above 75 degrees) I go with the sunglasses, because it gets hot fast.
I wore a Desoto Skin Cooler Beanie underneath for Abu Dhabi this year - admittedly conditions weren’t that hot - but it was plenty comfortable. Wore Oakley Radar Straight Stem glasses, which didn’t interfere with the ear flaps.
Having the shield must be more aero.
A visor is less aero actually, according to Mark Cote at Specialized: http://forum.slowtwitch.com/cgi-bin/gforum.cgi?post=3866581#3866581
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