The previous owner of my 1999 Southwind Class A (Ford F53 chassis) zip tied some cut to fit 1/8" square galvanized steel mesh to the back side of the front radiator grill. I painted it all flat black so it isn't really visible from the outside. So far, it seems to do a pretty good job of keeping road debris, bees, grasshoppers, butterflies and other flying pests off the AC condenser, the transmission cooler, and out of the radiator/engine bay. Even on the hottest days, overheating has never been an issue. I spray it clean with high pressure water from the inside as necessary.
I never drive in freezing conditions, but, I can see how it might be an issue with freezing rain, hail, or with large snowflakes. So far, so good.
Chum lee