Rescue dogs could go either way, so could a breeders. There will always be an element of luck of the draw where animals are involved. I guess research is key plus crossed fingers.
Nah, go for a rescue. Yes, it's a matter of chance but centres tend to know their dogs and will find a suitable one. And at least you haven't forked out a grand. You've given a donation to help other dogs and at least you know you'll have done some good,
My rescue dog is snuggled under my desk as I type this - she's intelligent, loyal, friendly and a great guard dog. I'd have really missed out if I hadn't picked her