What Kayak is really good in: If you have flexible dates. It shows you best fares found for each day. Otherwise I don't see why Sites like http://www.vayama.co

What Kayak is really good in: If you have flexible dates. It shows you best fares found for each day. Otherwise I don't see why Sites like http://www.vayama.com/ http://www.vayama.com/ or not the same. Besides the brand, what is their unique selling point? ebay, AirBnB has high entry levels. But a site to compare flights?