I found the interface easy to use with enough file conversion options available in addition to the PDF editors.

Buen servicioy desempeño

Has to be online, I loaded up some blueprint and it took a while for 8 pages. This has all the features I want but scrolling changes the size, and clicking and dragging is the only way to move around (which I hate).

Not necessarily a rating for this add-on, but the service of their website itself is excellent. I tried many other sites for converting PDF to other formats. This is the best I ever used. It is free, and most importantly, it values quality of the conversion. No major differences that I notice after converting some PDFs to PPTs, whereas most of other websites are either charged or compromised in quality (e.g. shifting of words).