Questions about Caucasians

[MSF]

We've been looking into LGD's and been told Caucasians are considered as such. However in an earlier post I read it seems they weren't really meant as such. (Or am I not reading right?)

We have a sweet pit bull and unfortunately she has been put in a position where she felt she had to protect my husband.
But it showed us she was capable. However she usually just goes up to cars pulling in the drive (Mail, UPS, folks lost and in the wrong driveway) and people wagging and thinking everyone is her very best friend. I don't want her nasty but I wish she would be more alert to caution. Maybe it is a wonderful thing she is such a sweetie yet when a true threat comes she changes to a totally different dog. 
Now that she is nearly 6 (and cause we also would like a LGD) getting a puppy now would be a good idea cause by time the pup is 2, Niki will be 8.

Anyway, as she gets older and I know her days will someday end, and due to us needing a LGD as well as a protector for us. I was wondering.

1) How do they do with strangers after they know they are ok?

2) Is there much of a difference between males and female?
(Protection ability)

3) Does spaying or neutering lessen their protective instinct?

4) How does someone go about finding a reputable breeder?
(PM me if you know of one)

5) Are their temperaments as extreme as a Fila?
(I had in the past checked into them and felt they were not for us)

I may have more questions later.
It would be nice to have one dog that can protect us as well as the livestock. We have folks coming up the driveway at times for the prior owners (who were of questionable nature-drugs) and I have a relative who is not emotionally balanced who leaved for months and sometimes years and then turns up on your door step unannounced that worries me. I love this person cause they are a relative but they frighten me and have behaviors that greatly concern me.

With what I have mentioned above would a Caucasian fit the bill?

[BabsT]

Hi,  I own a female CO and male CAO.  The main difference between the sexes with temp from what I am told is the male is less apt to show his feelings and female more emotional.   Nevermind the size...MY breeders male CO are just BIG.

I am not quite sure what you mean by strangers and ok... Zero my male CAO is aloof.. he wont look for trouble but he wont let you pet him, nor get to close to me.  My family and inlaws he is wonderful with but I still need to let you in the house, if you just open the door and walk in, that is not tolerated by Chara or Zero

If the dog is of correct temp, spay or neuter will not lessen their protective nature

Most filas are fear based (some people wont like to hear that) they work better in a pack vs 1 on 1.  Correct Fila stock is far and few inbetween and that is world wide.  That was told to me by very reputable trainers and would never recomment them.

You need fencing 6' and always a proper introduction with people.  My zero for instance...eve ryone that was in his life fairly often up until his 1st birthday he is ok with...the window is now closed with him... he doesnt like anyone else nor will he tolerate them in his house.

Chara is still maturing but she is reminding me more and more that she is a Caucasian LOL.  She is extremely alert to every sound sight or smell and she will hit the door with full force if she doesnt know who is behind it.

both dogs are wonderful with my family but you need to work with them everyday.  I personally will always have a CAO and CO in my house but the fur, barking, protection, digging, training, socialization is too much for most