Like another said, this is a Ford / Chevy / Dodge etc answer. A stock dog is hard to beat imo.
I'm a Border Collie guy. No crosses, just pure breds. Most of them have an internal drive that will not quit regardless of the weather conditions or the dogs physical condition. Whether on cows or playing with the kids in 100+ summer days, you will have to almost force them to stop and rest or drink. I've seen teeth knocked out of them from being kicked and they just keep working. Not as head strong as healers. They are slick coated with an under coat. The outer coat is almost waterproof, and they dry off incredibly quick. It also sheds dirt and brambles. Mine only bark when something isn't right. Not aggressive towards people, unless they sense the need to be. Very protective of my kids & wife. I watched from afar recently, when one of our 9wt steers tried to take my oldest son, my youngest collie cut it off instinctively.
In the end you get out what you put in to any dog.
I'm a Border Collie guy. No crosses, just pure breds. Most of them have an internal drive that will not quit regardless of the weather conditions or the dogs physical condition. Whether on cows or playing with the kids in 100+ summer days, you will have to almost force them to stop and rest or drink. I've seen teeth knocked out of them from being kicked and they just keep working. Not as head strong as healers. They are slick coated with an under coat. The outer coat is almost waterproof, and they dry off incredibly quick. It also sheds dirt and brambles. Mine only bark when something isn't right. Not aggressive towards people, unless they sense the need to be. Very protective of my kids & wife. I watched from afar recently, when one of our 9wt steers tried to take my oldest son, my youngest collie cut it off instinctively.
In the end you get out what you put in to any dog.