To answer your final question, yes but not really. You can definitely use AdWord keyword planner tool to get solid organic search volume estimates. However, don’t just stop there. Leverage other tools to find longer tail variations you can map against various stages of the buyer journey. I like to use SEMrush, Keyword and Google autosuggest.
Keyword Researcher is an easy-to-use Keyword Discover Tool. Once activated, it emulates a human using Google Autocomplete, and repeatedly types thousands of queries into Google. Each time a partial phrase is entered, Google tries to predict what it thinks the whole phrase might be. We simply save this prediction. And, as it turns out, when you do this for every letter of the alphabet (A-Z), then you're left with hundreds of great Long Tail keyword phrases.
These 3 keyword matching options are not solely to blame for the large variations seen when comparing data from the keyword tools. Much of this difference can be attributed to the distinctive techniques that the tools use to collect their data. Let’s take a look at how these tools collect and present their data and hopefully it will help clear up any confusion.
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.