The backlink index is one of the best too though at the time of writing, Moz has just improved their index. Regardless of index size, which theirs is large enough, the type of data they provide is the most useful. The broken links data is probably the most useful that isn't easily matched by other tools. Additionally, going back to the content explorer, you can find unlinked mentions, a feature that appears to have been removed in Moz's "new" tool (I may just not be able to find it).
Google Webmaster SEO Starter Guide - Originally written for Google Employees to improve website performance with users and search engines. Related Terms: SERP - Search Engine Rank Position | PageRank (PR) - Named for Google Co-founder, Larry Page. The PR Scale of 0-10 rates a web page. In the past, rank was based on the number of high ranking links pointing to the website. Recently factors like relevance and quality have gained importance. This website's current PR rating:
You can schedule a weekly technical SEO audit and our Site Audit tool will automatically start crawling your website. You’ll get a notification when it is finished in your inbox. By running website SEO audits on a regular basis, you are tracking the progress of your website’s health. With the Compare Crawls and History reports, and mini-trends on the Overview, Issues, and Page reports, you can analyze the results of different SEO audits and track changes in the number of issues over time.
It depends on the size of your operation, but I think you could get just as much value out of the Mangools Suite. This is the group in charge of KWFinder. But you can also take advantage of their SERP watcher and LinkMiner, and SiteProfiler features since you have an established business. They aren't quite as powerful as Ahrefs, but they get you 90% of the way for about 50% of the cost.
Depending on the plan, you are only allowed up to 100 domain searches a day. If you purchase their top tier plan you only get double of that. Sometimes it can take you several days to do certain types of research. This can start to get a little bothersome as we work with several clients and all of them need to use this software to make sure everyone is getting the best work that we have to offer.
Another advantage of using Ahrefs is their “Fresh Index” “Live Index” switch that displays backlinks that Ahrefs’ crawler found. The main difference between the two is that the Live Index is updated every 15-30 minutes to show live links in your site. For Fresh Index, it is updated at a much longer timeframe, but it still displays dead links which give you the chance to reclaim or change the dead link.