All geese can recognize people and identify who is good and who is bad. They're like dogs: if you socialize them enough they won't mind a stranger in the yard. If you don't then anyone they don't know will be screamed at.
Our old Embdens seemed louder than the Toulouse. Our big male was also the greatest guard dog we've ever had, and at times I wish we didn't get rid of him. He adopted any goose in the yard and made sure everyone was safe. I didn't lose a single gosling while free ranging when he was around. Embdens grow quickly and have a cleaner carcass when plucked.
Toulouse are also loud and protective of a yard. They lay more eggs than an Embden and dirt won't show up as much as with a pure white goose.
Both the Embdens and the Toulouse will greet you if raised with people. Any you keep in a meat pen will be aloof. Both are perfectly fine with other birds (though there's always the chance of an aggressive oddball, as with anything else). Embdens are more common than Toulouse (Toulouse are listed on the watch list put out by the ALBC).
Honestly, just go with the one that looks the prettiest to you. Embdens and Toulouse are almost interchangable as far as size, growth, temperment and eggs go. Unless you get the giant Embdens from Holderreads
If you do decide on both you'll need two separate pens for pure eggs if that matters to you. Geese may be loyal to one another, but they aren't above having flings from time to time.
PS:
http://www.albc-usa.org/cpl/waterfowl/africangoose.html
Quoted: "African geese are long-lived and will produce for many years under normal circumstances. If well managed, they will reproduce in their first year. Eggs are large, weighing 5-8 ounces, and hatch in 30-32 days (Holderread, 1986). Each gander can be mated with two to six geese, depending on the individual birds (Holderread, 1981). Africans produce high quality, lean meat, and are considered a premier roasting goose. Young ganders can weigh 16 to 18 pounds by the time they are 15 to 18 weeks old (Holderread, 1986)."
These guys aren't usually thought of as meat geese so I figured I'd toss them in. I'm not digging mine at the moment - they're definitely going to be louder than my favorite breeds. Plus I've already caught a couple hissing when upset. If it wasn't for one male I really like I'd move all of them to the meat pen.