Breed matters some but getting a great dog can be a bit of a gamble. Enough training can drastically improve the odds. Tons of people have had great success with adult rescues but I’m not willing to take the extra risk. You might get better than what you’re paying for but for me I like my chances better with a puppy for training. My daughter has two rescues and both are a pain. They’ve paid for training and followed training ideas Ive had success with but results have not gone great.