I get it what this tool trying to offer. If you have zero design bone in your body or just want to churn out some quick assets for non critical stuff then its fine. Not for you if you are even 1% a designer.
I tried hard to like it. But the lack of control over my design made me feel uncomfortable working with this tool.
Their own website do not have any feature information or any useful detail to judge it before anyone can try the tool.
All I can say is, the possibilities of creating any useful promotion/brand assess with this tool is very very limited.

Buy it if design don't matter a lot to your brand and all you need is quick and generic looking assets, posts and ads. Do not buy if you want customization and great looking assets.