I've tried as many as I came across but they are just useless bunch. Not worth.

If you want research + long form AI writing + (semantic) SEO in a nice holistic bundle, check https://longshot.ai/

For me the set looks like this, it's grammarly for convenience and Writesonic as a way to pad the text. I also sometimes look for new ideas in unusual places. For example, when I was writing an article about the documentary Babies, I read a bunch of essays with https://eduzaurus.com/free-essay... about it to form a small public opinion. I also used to search the forums for threads with the issue under discussion, which I need. In general, I try to work outside the box.

We've been using Jasper now for a couple of months which works quite well for researching and getting ideas for us