Illustrator is fine for letterheads, business cards, leaflets & flyers. We use Windows version CS6 .
With files with small amounts of text, it is sometimes worth converting all the text to outlines - this avoids any font problems. When saving, make sure “Create PDF Compatible File” is checked. Alternatively save the file in PDF rather than AI format.
If text is not converted to outlines, non standard fonts must be provided.
Images must be either embedded or supplied separately.