plastic caging opinions needed

[Mark]

I'm looking at starting to make plastic caging to start selling on top of melamine cages. I'm trying to figure out what people like best about them such as style,plexi/glass,size,sliding or hinged,stackable,litter dam and other issues about plastic cages. i'd really like some opinions if possible. I was looking at using HSPS(high density polystyrene(sp?) or pvc. I was leaning more towards the sliding glass such as on the vison cages and the rest of the cage build similar to the boafile ones.