They don't use bing for the most part, they have their own crawlers and their results are far better than nearly any other competitor. I have been a happy user

They don't use bing for the most part, they have their own crawlers and their results are far better than nearly any other competitor. I have been a happy user for the past two years. They use Bing for their ad network, and to sometimes (rarely) produce results when their own crawlers fail.