The initial document that I needed was insufficient on the site (the word SAMPLE was written across the document multiple times per page). And, although it took several hours, PDFfiller was able to upload the necessary document. Problem solved.

Performance is slow and choppy at times. There is no OBVIOUS way to turn off the popups every single time I go to fill out a form. Transitioning from one form to another is extremely disjointed. There is no clear way to fill out one form and simply move on to the next in a series. If there is a clean workflow in there somewhere, it's not obvious, at least, not for my use case, which is to fill out a form for each of my employees from a remote location, download all and print all for distribution. Seems like every time I finish something, it takes a while to save, and a while to get to the page letting me choose what to do next, which is always to display the file list again, and a while to load the file list. . .rather than simply keeping the filelist persistent and hidden, as would seem same here. Also, this form, won't let me enter more than a character or 2 before kicking me out. I am writing this feedback in a notepad and then copying it in all at once. Awesome.

I feel that it was inappropriate and a bit shady to let a customer edit the PDF and then hit them with the credit card ask. Maybe let them do a test for 15m or something.