My gripe with them is they are becoming invasive, like the autumn olive. And the new public enemy #1, bush honeysuckle. It's coming up everywhere.Many diss grafted ornamental pear trees, but the secret is to shape them early in their life. I planted this Bradford pear about 12 years ago, as a 6' B&B tree.
It's now about 30' feet tall, and has withstood ice storms, and 75mph winds. It's never lost a single branch.
Just took this photo late this afternoon. I'm especially fond of it's autumn color.