The Husky liner is a very tough product; don't knock it until you've lived with it. I have them for the front.
In the back, I wanted something rubbery and more comfortable for the dog to lay down.
I got this:
It will hold a certain amount of crud in the little circles but doesn't have a lip. It is very flexible, tough, and comfy for the dog ---- smelled like a skunk when new.
Nice product, perfect for me, but not for everybody.
Hope that helped...