Infighting only matters if you get caught up into it, and seems to be mostly the show crowd. The dogs don't know anything about it. I personally cross game bred APBT into my ABs and keep it at about 1/4. If you dont care more about papers than performance than the crosses are a good way to go.
2 cents.
you sound like my buddy in SC. She says the same thing. ABout your pit/ AB crosses. Are you using game bred stuff or stuff bred for catchwork? Do yo get a lot of dog aggression?