A beginner's perspective
I started using Outranking a few weeks before their recent update, and I have been lusting after an LTD like this since day one. Even before they rolled out their V5 with concepts it was good, specifically because of how useful having a steps framework with instructions interspersed has been for my still developing skill set. I’m basically a beginner moving toward intermediate at copywriting and blogging.
Since getting Outranking I have been vacillating between a few primary writing tools, it has essentially been a race between Outranking and Frase. I have had Frase for a while, but it has always been a bit confusing to use for actually writing. It has a less than intuitive workflow to me, though admittedly this is in part about my beginner status. I like Outranking a lot better for actually writing. It makes my workflow easier to keep track of, I am way more productive with it. When Frase rolled out their AI implementation I did go back and forth a bit, but when Outranking updated to V5 with concepts... I haven't used Frase since. Outranking in this current form is easily 3x faster for me.
From my perspective, if you're on the fence about this LTD, just try it out for an article and you'll likely be amazed. If you missed Frase and want something like it, this is better in my experience, especially if you're not already an accomplished writer.
As for the limits and which tier I would recommend, I cannot really comment on having a team of writers as it's outside my scope of experience. However, as a solopreneur that writes 1-2 articles per month using concepts, tier 4 would be sufficient. If you want to write an article a week or a bit more using concepts, probably tier 5 will be necessary. If you are not going to be using concepts much you might be able to get away with the lower tiers. I personally am going with tier 5 because even though currently I could get away with 4, I want a bit of room to grow.
Also, all the experiences I have had or seen with the Outranking team have been excellent, friendly, helpful and adaptable.
There are always risks involved in purchasing an LTD from a startup, but I feel comfortable with this one. Bottom line, this tool will pay for itself quickly if you have a use case and actually use it. So the risks are fairly low in the long run because your ROI is going to be easy to meet.