I recently decided to go with ahrefs after using spyfu for a couple years and trialing secockpit. I was a moz client for awhile too about a year ago. I found spyfu data to be sketchy (or just plain wrong) fairly often, and moz, I don’t know, just didn’t seem like they were really into supporting what I wanted to know. secockpit was achingly slow for a trickle of data. ahrefs isn’t nearly so graph-y as spyfu, but they are so blazing fast and the data is so deep. I enjoy it a great deal, even if it is spendy.
However, this does not mean you cannot topple them. It just takes more of an effort in terms of content as your page has to build the trust. That is why you will see the "Google dance" happening for fresh content from a site that is not yet trusted or is not very authoritative. Google gives your page a chance and measures user click-throughs when it pushes you to certain spots in the SERPs and then measures user engagement levels when the traffic hit your site through those positions in the SERPs.