Positive reviews from hundreds of users have shown that Long Tail Pro by Spencer Haws is the supportive tool available for internet workers. It is a reliable tool, which would help you to stay on top of your competition by ranking topmost on the search engines. You can test run the program before you buy it. It is highly recommended for every internet marketer.
It would be great if you can provide comparative analysis of this tool with Google Keyword Planner. Since you’re using this tool so you can provide best comparison. One differentiation which I understood is that this tool works for yahoo and bing as well whereas Google keyword planner works only for Google but Google being a dominating search engine, gives the highest returns, so only this reason may not be enough to buy it.