It's all breeds of dogs. Someone else's is always better. That's a plus for having a mixed breed 
 
 
We get it about two of our dogs- our Chi and our Westie. Westie's too small. Chi has too much fur (she's a longcoat). Blah, Blah, Blah. 
My two mixed breeds- all positive comments.  
I don't know why people feel a need to be like that about purebreeds.  
As a side note, my brother has a female boxer that is about 2. She's just over 50 pounds and she's a beautiful girl.