Bing is also a great source, if you want to generate some amount of traffic for your products and services especially after the tie up of Yahoo and Bing in search market. I am also using Bing as a second priority for my website.
According to me Bing is the best . We usually ignore Bing but according to my experience it will not take time to rank your website if you are doing well. Bing's result are little bit confusing but it is quite good.