I have two personal dogs currently, and no fosters. We have done the foster thing a few times... we have done small-time rescue for quite some time now, and have had a momma Pit Bull and 10 puppies along with personal dog, a crazy aussie shepheard, a deaf 8 year old abused English pointer, a rescued pom, and others... yikes...
My two dogs are Rosencrantz (Rosie) and Guildenstern (Guil).
One female, one male. Both rescues.
Guil is 5 now, is neutered, and has yet to have a problem with anything canine or alive that is not a squril.
He is a seasoned dog-park participater, and my live-in theripst for foster dogs...
Rosie is 8 months old, female, and also loves other dogs, both male and female. This could change as she matures, but I am somewhat doubting it.
Both dogs love puppies, thankfully.
My dogs are under constant supervision as someone is always home. They are left maybe 2 hours a week, seperated. We believe that all dog fights are preventable, and work hard under that theme.
I am very active with my puppy-pals, and we go on long walks, runs, and do a lot of biking together. When we are home they are usually sleeping or relaxing. Tired dogs are happy dogs, and all that jazz. It is a blast for me, as well... I am very active with obedience training (its fun for them and for me) so manners are good all around as well.
Having a dog of both sexes makes fostering a considerable effort, and I can only take in the "right' dog for the situation. I am currently not set up to keep dogs that cannot stand eachother properly seperated at all times.