To me...it sounds like you just don't want to do the work to get a full protection dog. The problem with not going hardcore into bite work and having proper bitework technique is that while training, your dog gets pressure tested, which is very important if a true attack is happening. There aren't many dogs that naturally will bite a human and will continue biting if that human fights back. Remember...a trained human, that is expecting a dog attack, can disable a dog. Without knowing that your dog will continue to bite when the attacker is punching/stabbing/kicking/chocking the dog, what's the point of having the protection dog if it will just run away the moment any kind of pressure like that is put on it.
Don't take this the wrong way...but especially because of where your dog comes from, there is no guarantee it will be good enough for this type of work. If you've ever seen a dog in drive during bite sport...you'd understand how hard it is to control them without proper obedience.
Anytime someone says they just want a PPD dog it worries me...mostly because of the amount of training thats necessary and because they probably don't completely understand how hard the training is. And its the training that tells the handler that the dog is ready and will do what is expected.
You should also know that if your dog is bite trained, and bites someone off your property, and you can't prove 100% that the person was going to hurt you. You've just lost your dog, and your house. If this is something you really want, you really have to be confident in the training that your dog receives because it does become a huge liability.