If you're focused on design and prototyping, especially in an environment that values openness and collaboration, choose Penpot. It excels for privacy-conscious teams and those who want to self-host their design tools. However, be aware that it has a smaller ecosystem and may not have the same level of polish as other proprietary options like Figma, which could be a concern if you rely heavily on plugins.
On the other hand, if your primary need is efficient and secure PDF processing, particularly for businesses with high document volumes, go with Stirling-PDF. Its strength lies in handling large amounts of PDFs in secure environments, making it ideal for organizations that prioritize confidentiality and document control. Just note that the cost can accumulate based on usage, and its mobile app capability is limited, which makes it less suitable for users needing robust mobile functionality.