I suspect the reason the pinlock shield says daytime only is due to the occasional 'double vision' you'll get at night when looking at other vehicles' headlights, restaurant lights, etc
Nope. It clearly said it's due to allowing less than 80% light transmission. Europe requires 80%, and the US and Australia 85%. But I don't see that as a problem at all, to be honest. By the way, the pinlock has a yellow tint, so good for night riding.
Maxtog, forgot to say another warning is the pinlock needs to be removed 'frequently', or it could ruin both the shield and pinlock by the silicone permanently getting stuck to the shield. I presume this is when the sun hits it in summer, I'd guess (plus also when an expanding pinlock can break the posts). Anyway, too many negatives for me to try it. And just found out can't put antifog spray on my glasses due to both reflective coating and transitions coating, so will not install the pinlock after all. And just rely on opening the vent and/or cracking the shield open if needed, like I've always done before.
Thank you all very much for your help. Will try the helmet as is and go from there. If not sure about a long trip, would just order the thinner center pad and carry it around in case it bothers my head. Have a good one.