I have two 7-mo GSD mixes that these are great for. My pups only sleep in these at night but they have been great at keeping them contained and comfortable. My escape artists are content in these and I sleep better knowing nothing inappropriate is being chewed while I sleep. I like that both doors can be opened for a more spacious feel in case they want to lounge in them during the day. These are heavy and sturdy. It took me an hour to put two together, very easy to construct.