I use simply Pledge to keep the visor clean of all the bugs & yes it has worked for many, many yrs. True Plexus is #1.
Still I also wax the helmet as well. One of the main tricks is to use a CLEAN SOFT COTTEN cloth & not the paper cloths as they will scratch the visor. Said cloths come from old & woren out T-shirts, sweat shirts, & other cotten clothing. Just cut into the size you want. I also carry them under my saddle with a plastic protectant like Pledge, Armor-All, 303, Plexus, the Turtlewax people & so many others. A new visor will probably outlive the helmet it kept cleaned. Least it does on my Shoei helmets. Yes the outside finish of my helmet are better in appearance then new products on the shelves.
Amazing things one can do with a little bit of inexpensive wax/&/or plastic protectant when used with a clean cloth.
Mind you the clean visor is more important to me then most of you as my left eye is fadding out of focus which effects depth of preception & any splattered bugs on the right side of my helmet's visor will cause me to halt & clean the visor from 2 to 6 times in a day of 4 to 8 hrs of riding on the hwys.