I prefer the classic, paper and pencil
Not with that attitude, you can't
I have probably logged about 3000+ hours in Adobe Photoshop. It is very powerful, Illustrator is also powerful, for vector graphics. I don't have very much use for vector graphics. But when I was actively running my design company, I would use both. A thing to note about Quark is they are adverting compatibility with .psd and .ai files. So that should tell you something. Again I haven't used Illustrator too much, but I have done some stuff for print, (eventual hardcopy), and I used primarily PS. So I would advice a highbrid of PS and AI for print work. I hope you win. ;)
If you need to do it in a timely manor then I would stick with what ever you are most comfortable with...<br />
Any vector app...<br />
I kinda like xara (but its vector input tools are a bit backward)...<br />
But then again its not as bloated as corel or as obtuse as illustrator..
I like photoshop
How about google sketchup?
The basic version is free.
Illustrator is for drawing, vector graphics. Quark xpress is for designing and layout of the book.