That's not quite the range of the Phantom 3 Professional, which managed 2,500 feet without issue, but it's better than the 1,000 feet I got with the Phantom 3 Standard in open space and the 400 feet it managed in suburbia.
Medical specialists with a public voice like Dr. Oz should absolutely be encouraging people who are sleepy to sleep more. However, arbitrarily applying eight hours to everyone is actually harming people who simply need less sleep, or those who actually need more than eight hours.
The average adult needs about seven to nine hours of sleep each night, according to the National Sleep Foundation, but most of us don't even get that much. But getting too little sleep -- generally understood to mean six hours or less a night -- can be serious -- enough to change your genes.