I think people's aresenal of keyword research tools are mostly the same: 1) You need a tool to examine search volume, most likely Google Keyword Planner 2) A tool to help you generate more keyword ideas. Tools that work with the search engines' autosuggestions are very popular such as KeywordTool.io and Ubersuggest 3) Then people might add a tool broaden the depth of their data, maybe including something like Google Trends or Moz's Keyword Difficulty tool.
How do I know that the KC score measures competition accurately? When I first started using the KC feature – I didn’t know for sure. But I’ve been using it since December of 2012. I’ve published literally hundreds of different articles (in different niches) around keywords with low to medium KC scores and I have a pretty good feel for the accuracy. More than 5 years of successfully ranking for low competition keywords has convinced me to completely trust the KC scores that are calculated within Long Tail Pro.

Keyword Researcher is designed to search the Autocomplete databases of Google, YouTube, and even Amazon.com. That's a lot of keyword sources! As you probably know, if you're building an authority site, or if you would like to become a dominant player in your niche, then starting with a large database of keywords (that your customers are actually typing in) is a powerful marketing tool.

Quick question… in your review you mentioned focusing on some products like ProductNamethat are spelled as Product Name and are low competition. My question is how would you tackle a review using a keyword like that? Would you make that the primary one that is misspelled? Would you mix them with the spaced spelling and correct spelling? I’ve found some good ones and would appreciate some direction on how you’d handle writing a post to rank for the spaced keyword?
I was paid approximately 2/3 of the funds upfront and will receive about 1/3 over the next 2 years.  It's now been almost 7 months since we closed the deal, and I've received the first couple of seller financing payments for that final 1/3 on time and am very confident that will continue for the next year and a half until I'm fully paid that final portion.
Long Tail Pro is a keyword research tool that helps you quickly find low competition keywords for your website.  In particular, the tool is built for people doing SEO (search engine optimization) as opposed to people doing paid ads (Google Adwords PPC).  I'm sure there are some advertisers that use the tool for paid ad keyword research, but the tool was built for SEO keyword research.