If you already create niche websites, you can clearly see how everything I’ve discussed above will benefit you. In fact, you probably already understood all of it. But maybe you are a blogger who has never thought of creating a niche website. Is this you? Let me tell you – if you can create a blog, you can create a niche website. It is not hard at all to create a small site, laser focused on a very specific topic, that will earn at least enough to make Long Tail Pro pay for itself.
Update: I’ve now been using Long Tail Pro for 5+ years. There are now many different keyword research tools and lots of people prefer some of the newer tools. Admittedly – Long Tail Pro had some hiccups and went through some rough times as they transitioned ownership and introduced the newer cloud version. But – all of the bugs and kinks have been worked out and Long Tail Pro is now better than ever! I’m happy and proud to be able to continue to use and promote Long Tail Pro as my keyword research tool of choice.

"This is the only keyword research tool that I recommend. The ideas, inspiration, and content longtails you will get for your niche topic are going to result in you producing a page of content that is more than going to pay for this tool. And as they are Google's database then we KNOW that these terms are being searched by a decent volume of peeps every month. It's a goldmine dudes."
However, KWFinder has a couple of areas where Longtail Pro outshines it. Firstly, I like the fact LTP provides you with a suggested keyword competitiveness to target (as described above). More significantly, I don’t like the way that KWFinder restricts your number of keyword suggestions if you choose their cheaper pricing tier – it feels like they’re holding back some of the power of the software unless you pay more. With LongTailPro, you can see as many keyword suggestions you like so long as you’re within your monthly allowance.
What are people looking for on your site? These terms are keywords in the vocabulary of your actual audience and should definitely be added to your keyword list. Do not forget to look at the keywords people filled in that didn’t get any results: this was stuff people were expecting but didn’t find. You can look into the results of your internal search in Google Analytics at Behavior → Site Search → Search Terms.
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.