Pros/cons of mPDF vs PDF in module PRINT?

First of all the PDF feature in the PRINT module is actually provided by MPDF, so it's not really a choice between PDF generation techniques, it's just how the MPDF library is used.

The PRINT module basically makes print and email versions of single nodes available, but from my reading of the project page it only makes those specific links available via node/nid/pdf. The print module does NOT appear to allow the ability to, for example, have a view created by the views module published as a PDF document, and it would not let you consume data from external data sources and have that data generated into a PDF document.

Certainly there is no reason not to use the print module in conjunction with forena, as the print module could be used to make a single page PDF view, but forena could generate multi-page PDF documents that included multiple nodes or site statistics or some other such reports.

Caveat: I have not tested this module, I'm just reading from the project page and making inferences, here. Hopefully that answers the question.

Clearly I should make an overview video regarding generating PDF documents, as there are probably a few best practice that should be documented. I really want to get the next version out the door though, so I'm not sure when I'll get to that.