I switched to DDG recently, have noticed no lag, enjoy the !g and !yt shortcuts (one less thing I have to set my browser up to do), and I really like how it puts Wikipedia at the top. But that's not why I switched: I don't want my web search queries to change my Suggested YouTube Videos. I noticed this recently with Google (since I'm always signed in). Sometimes a search is just a search, though, and it's almost like Google's slowly erasing that memory from reality.