I use DuckDuckGo as my default. The only time I ever have to revert to Google search is when I'm searching for things indexed within the past year. This is a pretty crucial feature when searching for technical items (ensures a good number of search results while also being relatively current). For some reason, DDG only lets you search up to the last month. If they added the ability to search within the past year, I probably wouldn't need to use Google search at all.