Hi, I do not have a mastiff yet, but admire them very much. I mean who wouldn't want a dog who was gentle, yet protective and easy to groom as well?? My husband has a senior lab and is thinking he might want a bullmastiff in the future, so I am going to be requesting information, to see if this would be a good choice for us. Right now, we have a senior lab and an aging German shepherd (my special girl, 13 yrs. old). Thanks.