That message was brought to you by a guy who's lost two Bradford pear trees in the last year for no other reason than they just ain't strong, durable trees.
Both instances involved the trees' crotches (actual terminology, btw) but that seemed highly inappropriate for this particular thread. Some other time, perhaps.
Bradford pears - grow fast (you get shade in, like, 30 minutes or less...), look great (the white blooms are gorgeous), last about 10 years or so and then give it up w/o too much resistance to the elements, and then not only do you lose a tree, but you got a pain-in-the-ass (and expensive, if you gotta hire somebody, more than the cost of a new tree) cleanup.
This last bigass storm we had, where the streets went from being paved in concrete to being paved by trees, damn near all of them was Bradford pears.