I am VERY concerned about purchasing from pdfforge as there seems to be a lot of confusion (or deliberate obfuscation) about the payment method, and the payment processing company.
If I buy a subscription, and then after a year or two decide to cancel it -- what happens to my copy of pdfArchitect?
if you purchase a PDF Architect Plan and cancel it, you won't be able to use it once your subscription has expired. You can however also purchase a perpetual edition which doesn't require any subscription: https://de.pdfforge.org/pdfarchitect/personal/perpetual
Of course, the perpetual edition is a little more expensive and doesn't easily enable usage on multiple devices, so if you are planning to use PDF Architect on more than one device or regularly rebuild your system/OS, the subscription makes more sense.
PDF Architect payments are processed by Upclick, while PDFCreator purchases are processed by Fastspring.