Both are great platforms.
To put it short, these platforms are surprisingly similar to one another, and if you have already used one, just stick with it. However, right now, based on a simple price check I did, I got cheaper video generations from Openart than Higgsfield.
Also, I favor Openart because it is easier to use, it has fewer outdated features, it has better and quicker support, and they offer the best models out there.
Please remember that if you are dedicated to only using one or two models out there and you don’t want to do comparisons or build more complex workflows, then just use those AI models directly from the official websites because it will be cheaper most of the time.