If you ship UI more often than once a quarter and your demos go stale because of it, CaptureBeam is the better fit. If your demos are mostly one-off marketing assets that don't need to be regenerated, stick with Screen Studio — it's a great tool and we're not the right answer for that workload.
If you're unsure, sign up for a month at $19.99 and run one demo through both the dashboard and the API. The first render goes up in under a minute; you'll know quickly whether the wedge applies to your team.