Analyzing the current top 10 search results in Google is the most important part of keyword research. This is where you determine whether or not you can produce a webpage that can beat any or all of those results. The process is known as first page analysis – and it is by far the hardest process to understand and really figure out (especially when you first start out). Don’t worry though – Long Tail Pro has detailed and in-depth instructional videos available that show you exactly how to do this.
If you don't know the difference between head terms and long-tail keywords, let me explain. Head terms are keywords phrases that are generally shorter and more generic -- they're typically just one to three words in length, depending on who you talk to. Long-tail keywords, on the other hand, are longer keyword phrases usually containing three or more words.
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.