Funny you should post this, right now I am looking at Great Dane rescues to adopt a Dane 6 years+. People take the senior dogs for granted... They're house trained, crate trained, often reliable to "free roam" in a room, eat less than puppies, already have their personalities, are much more mellow (not always, but most cases), and know most commands.
Sure, I love me a cute Dane puppy, but the costs to raise one is just through the roof and I'm not doing that again at this point in my life. I'd rather just bring an adult dog into my home ready to go to lunch with me and cuddle watching a good movie.