it's so much better than serpstat or seranking with the ranking. It's updated everyday. And it is fast. Very fast. Seems more accurate than the others.
What is brilliant is the feature of writing notes. The notes are attached to the days. So if you make changes on the website you can basically see what effect has this on your ranking. You can compare this with your notes.
If you buy more than one than use different email adresses. It's better than the stacking option. Would be awesome if they could integrate a good keyword searcher...