dwb wrote:
… and probably also jacked up the filesize of the image as well.
Not probably. The file size difference can be huge.
.pdf files are often only about 15-50k, sometimes less depending on subject, and stay sharp no matter what.
The equivalent .eps can be Mb/s and will also stay sharp but at best has a crude bitmap preview or none.
A converted .jpeg will be blurry and lack detail when enlarged and will be from 100kbs up to Mbs depending on the size and quality. It also has no transparent background.
By all means make your own tests but the principles and conclusions are clear.
The best format for vector files:
For flat areas of color or black & white images are .pdfs converted by Preview. These are often tiny files and remain fully editable.
For files with multiple blends and meshs .ai files saved from Illustrator with .pdf preview. These are bigger but maintain full editability whilst retaining all the benefits and features of .pdf files.
Peter