Never use anything on your shield that you wouldn't use on sun/eyeglasses or a TV/monitor screen.
I use Plexus for quick water beading but it's ridiculously expensive. If I want to "degrease" a shield/monitor/my phone I use eyeglass cleaner as it's designed for those really expensive anti-reflection treatments. I use it on my matte finish keyboard and mouse, too.
This is especially true for mirror finish shields. In fact, I only use soap and water on them with a light coat of pure carnauba wax (although I will be the first to admit that this is overkill). The first one I had (years ago) was cleaned with Windex and the mirror finish came off within a week... :x
I use a spray that we sell at my work and a microfiber towel. If you have a walmart they sell a cleaner in a small bottle that is refillable for free and it is safe for all glasses/shields even with AR coatings. It's only like $3.
I use those free hand sanitizer cloth dispensers in McDonalds in those dispensing drums provided by EcoLab. Works for the entire helmet plastic. Takes bugs, tar, sap, anything else off. I then take a napkin with a little water from the soda machine and go over it inside and out. I first leaned about this when I parked under a tree that dripped some kind of bug resin on my car. Worked well there too except I bought some and used some gauze squares in that situation. Then one day I stopped in and they were out, so I pulled off the lid and inside was a bunch of liquid, but no towelettes. I asked the manager what they did with that and he said Ecolab takes it away and puts in a new one, so he gave me about a quart of the stuff...enough to fill 2 of the large soda drink containers anyway. Not good to leave that stuff in soda cups so I labeled another container well and keep it in there.