Pros:
As far as functionality and reports, this is the closest one I've seen as far as a true SEMrush or Ahrefs alternative. Every tool will have differences in data, and both of those have been in business far longer so there will be some sites where you're going to get more information (more keywords, backlinks, etc) but for the sites I tested there's more than enough to plan content and identify link targets.

Compared to Ahrefs, which also operates on a credit system now, at least with this tool you have full access to all of the reports and features which is a big pro for me. While a lot of people think the credits run out too quickly, at least you're not completely restricted from being able to run certain reports which is the case on the least expensive Ahrefs plan.

Cons:
I'll be more specific and not complain about the credits, but I'll say the lack of tracking and caching is a con here. For the developer and for customers, it would be cheaper on all sides if more reports were cached. At most, I'm guessing some of the information changes on a weekly basis, but more than likely it's only updated on a monthly basis. I believe they charge credits even if you're just rerunning the same report because they're doing a fresh pull on the information with each request. This is something even the established tools have had to deal with. I know in SEMrush there are some keywords where you have to manually trigger a refresh of the data if it's not a keyword you're tracking, so providing cached data as the default is actually very common. Hopefully improvements in this regard are on the roadmap. For popular search terms - meaning someone else requested information within the last few days - this would reduce costs so that fresh pulls and credits could be reserved for long tail and more specific keywords. This is the main reason I can't give it 5 tacos.

Overall, I'm hopeful that the tool will continue developing because they're currently charging enough with the credit system to make it sustainable. It would help to know how much a run of each report will take ahead of time so that people can plan out how they want to use what they have, especially on the lower tiers. From someone who's worked with SEO tools for over 15 years though, definitely one of the most promising SEO tools I've seen at an overall good value especially if you're doing SEO for your own site or a small number of clients.

Minor Quibble: The Keyword Difficulty score calculation isn't great. It's not something that I think any tool really gets right, and I tend to check out SERPs myself to figure out what the real difficulty would be as a rule. But there are a lot that are being reported as much lower in difficulty than they are at a pretty high degree. If you're someone who actually pays attention to those scores, you may find them misleading or unreliable.