Yahoo Search is already powered by Bing – since 2009.[1]
At first I tried scraping DuckDuckGo but couldn't because my IP was being recorded at some point where it was being throttled. So I looked a little deeper and found the sources of their search data. So I use the services listed above directly.
lol I didn't realize that the Yahoo image search was powered by Bing. The web based search for images return the same, however, the APIs are returning different image sets. The Yahoo version is better.