If you actually mean the library (for .NET) — that’s for generating PDFs, not primarily watermarking. But if you searched “quest pdf watermark,” you probably want a dedicated watermarking tool.
If you clarify the exact software name or link, I can give a precise review. quest pdf watermark
(hypothetical for a decent watermark tool): 3.8/5 – works fine for basic needs, but advanced users may want more control. If you actually mean the library (for