Is my long tail keyword research being done correctly?

I use two different programs to help me pick my long tail keywords. First I use Long Tail Pro and select at least 5-word terms that have a "Keyword Competitiveness" score of 30 and under. If they pass that test I take the same word and go to ahrefs and then see if the term has a "Keyword Difficulty" score of 15 or under. Does anyone here do something similar? Should my competition numbers be for both be lowered? Thanks.

Most 5 word terms should be considered relatively easy unless it's something truly specific.

To be sure though, just check the precise term at adwords.

5 keyword long tails are relatively easy to rank, as long as they define their own category, but sometimes things get tricky.

best wireless router of all time has almost the same competitive difficulty as best wireless router. Mostly, the same websites appear in top, since the extra words are just filler words. So you also need to use a little bit of common sense when evaluating the niches and see if it makes sense for you.

I think there is more value in evaluating the top 10 results individually and see how many weak websites you find, rather than relying to much on metrics as the final answer. Metrics like KC or KD are good as a general indication, but without a manual look at the top results, you can still miss sometimes.