Searches on SideStep to several citiers turned up less than a dozen entries. SideStep is legally precluded from spidering Expedia (EXPE), Sabre's Travelocity, or Cendant's CheapTickets, so to call this outfit the Google of travel isn't really accurate. You're still missing out on a ton of inventory if you just rely on them - particularly when it comes to hotels. Searches to several sites turned up less than a dozen entries. Even on flights, several searches showed that the traditional sites are occasionally cheaper, and they have features SideStep lacks, like multi-city search.

Still, SideStep comes closest to making me happy out of any travel site I've ever used. It aggregates listings from thousands of sites, including ones that also share listings with the traditional online travel agents and ones like JetBlue that do not. So overall, you're getting a better selection, even if you may miss out on a few deals.

And then there's the user interface. I love it. All travel sites can be buggy. But in my tests, it was always faster than other travel searches and crashed far less often. It automatically searches airports near your point of departure or destination, and has an easy-to-use left-hand navigation bar that can slice and dice hundreds of flights by price, number of stops, when the flight leaves, or carrier.

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