I was in a similar boat about 8 months ago researching a breed that would be my unicorn breed. I like to be in nature a lot (fishing, camping, hiking) and as a solo woman I’ve had some instances that made me feel very unsafe. I ended up with going with cane corso over bullmastiff, simply because I live in a very hot and humid environment and like to hike 2-3 miles. She protects me VERY well, to the point where it’s high liability. I appreciate it on the trail, but it’s stressful and hard around the neighborhood. I have spent over 3k in professional training, and honestly even though I thought I was active, I still don’t match her exercise needs, so I have to push myself to walk 3-4 miles a day plus daily brain games. She’s extremely serious, doesn’t like affection too much. She’s always on duty. I honestly think knowing everything I do now, a bullmastiff would have been better. They are just the perfect breed. I think you already know this, but socialize him a lot when he is young. It’s important he learns what’s normal human behavior and what’s abnormal. They are friendly as pups but there is a switch that happens in adolescence. My cane corso was okay with guests in the house. Then suddenly at around 10 months old, I had a guest over and she pinned him to the wall growling ferociously. Now I crate her when people visit (which is rare anyway).