There is no budget for me to study into Acrobat’s pdf editor in detail, so, I do not know whether PdfEdit is weaker or stronger than it.
But based on my experience, I just recommend PdfEdit as your pdf editor, especially if you do not bother do a little script programming.
Here, I give an example of how could you change all pages’ size with PdfEdit.
Step2: goto 1st page again, if you want to change page 1-6′s size to (50,0,595.2,841.92), then input the scripts to script window and press enter to execute it, that’s all:
For more samples of PdfEdit script, you can refer to .ps files in PdfEdit home dir, e.g., ubuntu install it to /usr/share/pdfedit/.
Detailed script API can be found at: http://pdfedit.petricek.net/appendix.html