Bear in mind that the numbers being compared above are the cost for the exact same seat on the exact same plane with the exact same airline. (travelingformiles.com)
So these two companies, Orbitz and Hotwire, were started at about the same time by about the same airlines but had very different governance. (businessinsider.com)
These are best if you're an avid traveler and consistently book with the same airline or hotel. (valuepenguin.com)