We currently have Standard version of Nintex Forms and Workflows, We have created a Nintex Form and one of the requirement is to PRINT to PDF adjust the page layout etc. We wanted to trail for 30 days to see if the user requirement is fulfilled with Enterprise version before we purchase.
you can get a trial version here (Get started with Nintex) or get in touch with your Nintex partner.
I suggest you test it on a test environment though. You could add it to your production environment and replace the test license again with your original standard license before test period ends. But going this way you need to ensure that no one uses enterprise features in workflow or forms as they will break when you fall down to standard.
So I think testing this on a testing environment is the better way.