I used moz and I thought that this is better than ahref. It gives the right keyword difficulty and traffic. According to my testing. where's ahref shows wrong data it provides less keyword difficulty then it is actually. what are you using. I want to stick to better tool for long term.
Note:- All my efforts towards better tool.
Not a single tool will give you an "accurate" measurement of any metric.
They all use different methods, formulas, and algorithms to come with a KD score or to a monthly search volume. In the end, it´s YOU that needs to run your own research and go beyond those metrics.
Personally, I use KD scores just to filter out results but I ALWAYS conduct my own KD assessment by running a SERP analysis. I found this to be the best approach to fully realize what is the true keyword difficulty or to determine the likelihood of you ranking on the first page of all-mighty Google.
So, going back to your original point, I´ve used Ahrefs, SEMrush, KWFinder, Keywords Everywhere, SERPStat, SERanking, and Keysearch and among all those tools I would choose Ahrefs for keyword research if the budget wouldn´t be an issue for me and I could afford it on a monthly basis.
But, personally, I think Keywords Everywhere is the best and most cost-effective keyword tool on the market today. I purchase 100,000 credits for $10 over a month ago and I still have around half of those credits I´ve brainstormed thousands of keywords and long-tail variations.
I FREAKING LOVE IT!
