I've used both bing, google, duckduckgo, altavista (when it was around), etc. Personally, I don't have a favorite. So long as I get to the data I'm looking for, I don't really care which search engine got me there.
Every time I see a question about bing vs google vs whatever, I always state the same thing, use the one that gets you to your data quicker. If that is bing, great! use it. If that is google, awesome! use it.