I actually think it's less maintenence... but to each their own!
The mesh grids I have are just like the mesh ones(not the gird ones, but the mesh in the middle) in the link PiggieMom provided.... but they are SO hard to find. I got mine about a year ago at a Bed Bath and Beyond (or maybe it was Linens and Things?) during a store close out sale.
Maybe you could make your own? I bet if you got some screen material(like they have on windows) and made some kind of frame and attached the screen to it, you would get something you could see through, would have good ventilation, and keep mess inside!
I don't know how well it would work, I'm the worlds worst builder!
But just a thought!