All WORKING DOGS are GOOD GUARD DOGS . WHat you need to consider is the TEMPERAMENT of the dog you are going to get because the puppies temeperament would reflect on who are the parents and their background and line if you are really serious of having a SECURITY and GUARD DOG .
I chose the DOBERMAN because of the low maintenance it requires raising it . Lesser trips to the groomer and very affectionate to the members of the household not to mention its loyalty . Not all DOBIES have good temperament , mine got a good one considering its a Lex Luthor line . Cuba knows if its hostile or friendly , when to be protective and when to be relax at the same time alert even at the young age of 11 months old . Very playful to children also . Let me know if you are interested to acquire a DObie of the same lineage .