I've used crate training on two of my three dogs and I'm not that keen on it. Some dogs just never adjust to it. I have a 14 week old puppy right now and she cries for 15 minutes every time you put her in a crate; she hates being crated. She wakes up during the night and cries and wakes me up too.
Crate training works for some dogs but not all. And I don't believe dogs she spend hours and hours in a crate. It's not healthy psychologically I'm sure.