Every take you keep unlocks the clean, full-quality file: no watermark, yours to download and use anywhere — commercial work included. Client projects, ads, products, social — all fine.
This doesn't change with your plan. Free keeps export exactly as clean as Ultra keeps; only locked previews carry a watermark.
If you cancel your subscription, everything you kept remains yours. The license on a kept take doesn't expire with the plan that paid for it.