The cost is only a one time payment…no monthly fees, which is fantastic if you’re on a budget, and you get lifetime updates and some truly excellent training videos as well as some very useful built-in tools. I’ve also tried other paid keyword tools such as Market Samurai, Wordtracker, Jaaxy, and others, and let me tell you this….none of them come close to Keyword Researcher Pro for value and ease of use.
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.