I have a metal mesh on my car, it came in rust proof silver, but I painted it black and it looks great....even at different angles you can't really see behind the mesh....
the holes in teh mesh are like 1/4" x 1/4" maybe even a little smaller. Took me about 30 minutes to do the upper grill and the fog lamp areas....all mine are moulded too...so they are flush with the flow of the bumper when you look at it.
Here are some pics:
The top pic: most recent frontal shot (but in partial shade, sorry).
The middle pic: the mesh looks wierd because it's still wet from washing the car.
The bottom pics: before I put mesh in, and before I painted the mesh black.